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Results for https://ted.com

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Netherlands Netherlands · Amsterdam Completed: Apr 16, 2026 17:58 UTC
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Mobile 375 × 812

Screenshot of the audited page (Mobile 375×812)

Desktop 1440 × 900

Screenshot of the audited page (Desktop 1440×900)
D69

Site Health

Score: 69 / 100

Based on 8 categories, 0 sections

Room to improve — your 17.3s load time is above Google's 2.5s 'Good' threshold.

Several missing protections leave your users and data exposed.

Several issues make your site difficult for assistive technology users.

Well-optimized for search — your content is discoverable.

Solid infrastructure — fast server responses across the board.

Mostly compliant — a few items need attention.

Good content signals with minor gaps.

Heavier than average — reducing page weight saves energy and bandwidth.

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

How the composite score is calculated

How you compare

CMS sites average 73
At average
Better than 2% of CMS sites
Amazon Route 53 sites average 72
At average
Better than 8% of Amazon Route 53 sites See full Amazon Route 53 benchmark →

Top Priorities (5)

1

Content-Security-Policy header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers
2

No Content-Security-Policy header found

Security gaps expose your site and users to attacks, eroding trust.

Security › Content Security Policy
3

Page weighs 41.9 MB (29.6 MB transferred)

Performance issues directly impact user engagement and conversion rates.

Performance › Page Weight Budget
4

1 control(s) without accessible label

Accessibility issues exclude users with disabilities — up to 15% of your potential audience.

Accessibility › Form Accessibility
5

1 image(s) missing alt attribute

Accessibility issues exclude users with disabilities — up to 15% of your potential audience.

Accessibility › Alt Text Quality
View fix priority matrix

Fix Priority Matrix

5 findings

Quick Wins

2

High impact, low effort — start here.

Strategic

3

High impact, requires investment.

Easy Improvements

0

Small gains, minimal effort.

Nothing in this quadrant — good news.

Deprioritize

0

Low impact, high effort — do last.

Nothing in this quadrant — good news.

← Low effort High effort →
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What fixing these means

Your site has several issues that may be affecting user experience and business outcomes. Your LCP of 17.3s exceeds Google's 2.5s 'Good' threshold and the 1 performance issue below directly contributes to it. Accessibility issues exclude users who rely on assistive technology — an estimated 15% of your potential audience. Addressing the critical issues below would have the most immediate impact on your user trust.

2 security gaps detected — browsers may warn visitors about your site.
Your LCP is 17.3s — fixing the 1 performance critical could bring it under Google's 2.5s 'Good' threshold.
2 accessibility issues exclude users who rely on assistive technology.
C
Could reach Estimate based on resolving critical issues

Conversion Barriers

3 critical 7 warning

10 barrier(s) likely increasing bounce by ~33%.

Speed (2)

Page takes 17.3s to load

+12% bounce

Users abandon at ~3s — you're 14.8s over the 2.5s threshold

Fix: Optimize render-blocking resources, preload the hero image, and compress images

Page feels frozen for 12.5s

+5% bounce

Clicks on the primary CTA are ignored while JavaScript runs

Fix: Break up long tasks; defer non-critical JavaScript to post-hydration

Trust (2)

No HSTS header

+1% bounce

Returning visitors are briefly exposed to downgrade attacks on first request

Fix: Set Strict-Transport-Security: max-age=31536000; includeSubDomains

No Content-Security-Policy header

+1% bounce

Higher XSS blast radius — one compromised script can exfiltrate the checkout form

Fix: Ship a reporting-only CSP first, then enforce once violations are clean

Usability (2)

1 form field(s) without a label

+2% bounce

Screen readers skip unlabeled fields; autofill can't identify them; checkout abandonment spikes

Fix: Associate every input with a visible <label for="…">; add autocomplete attributes

Viewport disables user zoom

+2% bounce

Visitors with low vision can't read the page — and some jurisdictions treat this as a legal risk

Fix: Remove user-scalable=no; drop maximum-scale if it's below 2

Content (1)

No structured data

+2% bounce

No rich-result eligibility in Google — lower SERP CTR vs competitors with stars and prices

Fix: Add JSON-LD for your page type (Product, Article, FAQPage, LocalBusiness, …)

Navigation (3)

14 link(s) with generic text ("click here", "read more")

+1% bounce

Screen-reader users navigating by link list see no context — and search engines can't infer relevance

Fix: Rewrite with descriptive phrases that identify the destination

No skip-to-content link

+1% bounce

Keyboard and screen-reader users must tab through the entire header on every page

Fix: Add a visible-on-focus <a href="#main">Skip to content</a> as the first focusable element

6 broken link(s) on the page

+5% bounce

Clicks land on 404s — trust drops and the session often ends

Fix: Fix or remove the broken destinations surfaced on the Content tab

Preliminary CRO audit — each barrier links to the tab with detailed analysis.

Return on Investment

€510 investment → €6.89/month returns + EUR 120,500,000 risk avoided

Payback period: > 2 years First-year ROI: -84%

Investment

€510

6h · 5 findings

Monthly returns

€6.89 /mo

~€83 / year

  • Bandwidth savings €6.89

Regulatory risk avoided

EUR 120,500,000

if kept compliant

  • ePrivacy Directive EUR 100,000,000
  • GDPR EUR 20,000,000
  • EAA EUR 500,000

€85 — in quick wins — start here for the fastest payback

Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.

Full methodology & sources

Estimated Remediation Cost

€510

6.0 developer hours at €85/hr

Based on European Union rates (€85/hr)

Quick wins
€85 2 fixes in ~60 minutes

Start here for the best return on investment

Cost by category

Cost by effort level

Adjust assumptions
/hr

Rates reflect fully-loaded developer cost including overhead

How developer rates are sourced

What Inaction Is Costing You

€10,041,674 / month at risk

~€120,500,083 / year if left unfixed

Compliance Risk

€120,500,000

ePrivacy DirectiveGDPREAA
  • No privacy policy link detected
    GDPR: EUR 10,000 – EUR 20,000,000
  • 4 advertising/retargeting trackers detected
    GDPR: EUR 10,000 – EUR 20,000,000
  • Trackers detected but no cookie policy found
    GDPR: EUR 5,000 – EUR 10,000,000

+10 more

Bandwidth Waste

€6.89 /mo

92995.1 MB/mo × 0.074 EUR/GB

  • Optimize transfer: save ~9.3 MB per page load
    Saves €6.89/mo

Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.

Compliance methodology · SEO assumptions · Bandwidth model

Your performance is already good — improvements may show diminishing returns

Unique monthly visitors from your analytics

Purchases, signups, or key actions

Optional — for revenue estimation

additional conversions/month

more engaged visitors from reduced bounce

potential monthly revenue
Current bounce (est.)
After fixes (est.)
Estimated bounce reduction

Fix 5 critical issues to capture this value

How this is calculated

Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.

Your site's LCP: → estimated after fixes.

These are estimates based on industry research — actual results vary

Bounce-rate model & assumptions

Your data stays in your browser — nothing is sent to our servers

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

32
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
76
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

2.39 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

17.28 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

12.45 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.052

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

17.39 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

46.47 s

Detailed Report

Audit breakdown by category with detailed findings.

32

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
pl.tedcdn.com/fonts/InterVariable.woff20.0 ms344.6 KiB
/fss/fve7g7/b69e7dfa-6829-4033-8ec2-a82ec67eaceb/TEDGAMES...0.0 ms192.3 KiB
cdn.yourbow.com/ted/hbyb.js3600.0 s196.3 KiB
cdn.fundraiseup.com/widget/AVFWZGUV0.0 ms65.3 KiB
ak.sail-horizon.com/spm/spm.v1.min.js600.0 s48.1 KiB
b-code.liadm.com/a-091g.min.js86400.0 s47.0 KiB
cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js86400.0 s29.1 KiB
static.cdn.prismic.io/prismic.js?new=true&repo=tedconf0.0 ms9.8 KiB
cdn.rudderlabs.com/3.21.0/modern/plugins/rsa-plugins-RetryQueue.min.js3600.0 s3.9 KiB
cdn.rudderlabs.com/3.21.0/modern/plugins/rsa-plugins-common.min.js3600.0 s3.6 KiB
vz-8bbc7bbf-a1e.b-cdn.net/44455006-1a54-4b23-bfe8-c6187b9478d5/720p/video.m3u830.0 s1.8 KiB
vz-8bbc7bbf-a1e.b-cdn.net/44455006-1a54-4b23-bfe8-c6187b9478d5/480p/video.m3u830.0 s1.8 KiB
vz-8bbc7bbf-a1e.b-cdn.net/c0618340-2751-4cb8-bcbd-3992c694dac3/480p/video.m3u830.0 s1.8 KiB
vz-8bbc7bbf-a1e.b-cdn.net/c0618340-2751-4cb8-bcbd-3992c694dac3/720p/video.m3u830.0 s1.8 KiB
vz-8bbc7bbf-a1e.b-cdn.net/42e70133-846c-4d82-b891-6715daa034dc/480p/video.m3u830.0 s1.7 KiB
vz-8bbc7bbf-a1e.b-cdn.net/42e70133-846c-4d82-b891-6715daa034dc/720p/video.m3u830.0 s1.7 KiB
vz-8bbc7bbf-a1e.b-cdn.net/bde3fe3d-fa23-4257-b5bb-c42dfa9086eb/480p/video.m3u830.0 s1.6 KiB
vz-8bbc7bbf-a1e.b-cdn.net/bde3fe3d-fa23-4257-b5bb-c42dfa9086eb/720p/video.m3u830.0 s1.6 KiB
vz-8bbc7bbf-a1e.b-cdn.net/49a16d6c-9839-438c-a814-ee646f5b515f/480p/video.m3u830.0 s1.4 KiB
vz-8bbc7bbf-a1e.b-cdn.net/7740cf90-8213-4c38-8b2f-68813d73045d/480p/video.m3u830.0 s1.4 KiB
vz-8bbc7bbf-a1e.b-cdn.net/49a16d6c-9839-438c-a814-ee646f5b515f/720p/video.m3u830.0 s1.4 KiB
vz-8bbc7bbf-a1e.b-cdn.net/d8644e4c-8639-4796-b1fa-8eacec07c26a/480p/video.m3u830.0 s1.4 KiB
vz-8bbc7bbf-a1e.b-cdn.net/d8644e4c-8639-4796-b1fa-8eacec07c26a/1080p/video.m3u830.0 s1.4 KiB
vz-8bbc7bbf-a1e.b-cdn.net/7740cf90-8213-4c38-8b2f-68813d73045d/1080p/video.m3u830.0 s1.4 KiB
vz-8bbc7bbf-a1e.b-cdn.net/a1599794-4c67-4c14-9161-d08bf188b37c/480p/video.m3u830.0 s1.4 KiB
cdn.rudderlabs.com/3.21.0/modern/plugins/rsa-plugins-remote-XhrQueue.min.js3600.0 s1.6 KiB
vz-8bbc7bbf-a1e.b-cdn.net/e921c045-0f6e-4a88-a7cc-0695fa6b5153/480p/video.m3u830.0 s1.2 KiB
vz-8bbc7bbf-a1e.b-cdn.net/e921c045-0f6e-4a88-a7cc-0695fa6b5153/1080p/video.m3u830.0 s1.2 KiB
vz-8bbc7bbf-a1e.b-cdn.net/a442ca3a-9e00-40c5-8a76-33ee6472d589/480p/video.m3u830.0 s1.1 KiB
vz-8bbc7bbf-a1e.b-cdn.net/a442ca3a-9e00-40c5-8a76-33ee6472d589/720p/video.m3u830.0 s1.1 KiB
vz-8bbc7bbf-a1e.b-cdn.net/44455006-1a54-4b23-bfe8-c6187b9478d5/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/bde3fe3d-fa23-4257-b5bb-c42dfa9086eb/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/7740cf90-8213-4c38-8b2f-68813d73045d/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/e921c045-0f6e-4a88-a7cc-0695fa6b5153/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/42e70133-846c-4d82-b891-6715daa034dc/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/a442ca3a-9e00-40c5-8a76-33ee6472d589/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/a1599794-4c67-4c14-9161-d08bf188b37c/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/d8644e4c-8639-4796-b1fa-8eacec07c26a/playlist.m3u830.0 s1.0 KiB
vz-8bbc7bbf-a1e.b-cdn.net/49a16d6c-9839-438c-a814-ee646f5b515f/playlist.m3u830.0 s934 B
vz-8bbc7bbf-a1e.b-cdn.net/c0618340-2751-4cb8-bcbd-3992c694dac3/playlist.m3u830.0 s933 B
cdn.rudderlabs.com/3.21.0/modern/plugins/rsa-plugins.js3600.0 s990 B
sli.ted.com/baker?dtstmp=17763621716280.0 ms536 B
/usersync/liveintent/?cb=//i.liadm.com/s/35004?bidder_id%...0.0 ms200 B
cdn.fundraiseup.com/embed-data/elements-global/AVFWZGUV.js0.0 ms174 B
match.adsrvr.org/track/cmf/generic?ttd_pid=liveintent&ttd_tpi=1&gdpr=00.0 ms149 B
vz-8bbc7bbf-a1e.b-cdn.net/a442ca3a-9e00-40c5-8a76-33ee6472d589/480p/video.m3u830.0 s0 B

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:201.401 source:map[column:137515 line:1 type:source-location url:https://www.ted.com/_next/static/chunks/10ve7kro4jeja.js urlProvider:network]]]
headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:137.084 source:map[type:text value:[unattributed]]] map[reflowTime:77.321 source:map[column:4871 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:152.117 source:map[column:26857 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:2.268 source:map[column:33340 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:10.045 source:map[column:34152 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/12yqivmg51ele.js urlProvider:network]] map[reflowTime:5.038 source:map[column:27358 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:10.917 source:map[column:30031 line:1 type:source-location url:https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js urlProvider:network]] map[reflowTime:3.43 source:map[column:62355 line:1 type:source-location url:https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js urlProvider:network]] map[reflowTime:0.966 source:map[column:62714 line:1 type:source-location url:https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js urlProvider:network]] map[reflowTime:3.171 source:map[column:26 line:803 type:source-location url:https://media.begenuin.com/sdk/chunks/vendor-external-O5cr870B.js urlProvider:network]] map[reflowTime:21.853 source:map[column:40 line:8184 type:source-location url:https://media.begenuin.com/sdk/chunks/vendor-animation-Cov7gVAf.js urlProvider:network]] map[reflowTime:24.662 source:map[column:86 line:8419 type:source-location url:https://media.begenuin.com/sdk/chunks/vendor-animation-Cov7gVAf.js urlProvider:network]] map[reflowTime:31.033 source:map[column:15 line:7691 type:source-location url:https://media.begenuin.com/sdk/chunks/feed-C4rzC3fy.js urlProvider:network]] map[reflowTime:9.537 source:map[column:20327 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]]]

Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:label label:Subpart valueType:text] map[key:duration label:Duration valueType:ms]]
items: [map[duration:375.338 label:Time to first byte subpart:timeToFirstByte] map[duration:1923.054 label:Resource load delay subpart:resourceLoadDelay] map[duration:94.971 label:Resource load duration subpart:resourceLoadDuration] map[duration:349.42 label:Element render delay subpart:elementRenderDelay]]
lhId: page-0-IMG
nodeLabel: Promo image
path: 1,HTML,1,BODY,1,DIV,1,DIV,1,DIV,1,MAIN,0,DIV,0,SECTION,0,SECTION,0,DIV,1,DIV,1,DIV,0,DIV,0,A,0,IMG
selector: div.swiper-slide > div.relative > a.block > img.object-cover
snippet: <img alt="Promo image" loading="eager" decoding="async" data-nimg="fill" class="object-cover object-top" sizes="(min-width: 1920px) 33vw, (min-width: 1024px) 50vw, (min-width: 768px) 66v…" srcset="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad1DqZ1ZCF7ETJlO_TEDLive…" src="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad1DqZ1ZCF7ETJlO_TEDLive…" style="position: absolute; height: 100%; width: 100%; inset: 0px;">

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-IMG
nodeLabel: Promo image
path: 1,HTML,1,BODY,1,DIV,1,DIV,1,DIV,1,MAIN,0,DIV,0,SECTION,0,SECTION,0,DIV,1,DIV,1,DIV,0,DIV,0,A,0,IMG
selector: div.swiper-slide > div.relative > a.block > img.object-cover
snippet: <img alt="Promo image" loading="eager" decoding="async" data-nimg="fill" class="object-cover object-top" sizes="(min-width: 1920px) 33vw, (min-width: 1024px) 50vw, (min-width: 768px) 66v…" srcset="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad1DqZ1ZCF7ETJlO_TEDLive…" src="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad1DqZ1ZCF7ETJlO_TEDLive…" style="position: absolute; height: 100%; width: 100%; inset: 0px;">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

More than 4 preconnect connections were found. These should be used sparingly and only to the most important origins.
description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
Promo image div.swiper-slide > div.relative > a.block > img.object-cover
/r/images.prismic.io/tedconf/ad1DqZ1ZCF7ETJlO_TEDLivehome...503.2 KiB417.8 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/7740cf90-8213-4c38-8b2f-68813d73045d/thumbnail_47deaab8.jpg424.3 KiB382.0 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/bde3fe3d-fa23-4257-b5bb-c42dfa9086eb/thumbnail_12373bac.jpg420.2 KiB377.9 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/d8644e4c-8639-4796-b1fa-8eacec07c26a/thumbnail_830e788d.jpg418.8 KiB376.5 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/a442ca3a-9e00-40c5-8a76-33ee6472d589/thumbnail_b0c7edff.jpg406.4 KiB364.1 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/c0618340-2751-4cb8-bcbd-3992c694dac3/thumbnail_e067781e.jpg381.2 KiB339.0 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/a1599794-4c67-4c14-9161-d08bf188b37c/thumbnail_5ab14752.jpg424.3 KiB317.4 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/44455006-1a54-4b23-bfe8-c6187b9478d5/thumbnail_d2276f67.jpg419.2 KiB312.3 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/49a16d6c-9839-438c-a814-ee646f5b515f/thumbnail_9a7724e0.jpg410.9 KiB304.0 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/e921c045-0f6e-4a88-a7cc-0695fa6b5153/thumbnail_b29f394e.jpg405.9 KiB299.0 KiB
div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto div.swiper-slide > div.gencl:h-full > div.gencl:relative > video.gencl:w-auto
/42e70133-846c-4d82-b891-6715daa034dc/thumbnail_7bf13db5.jpg377.2 KiB270.3 KiB
ted_idea_search_buenos_aires_argentina a.relative > div.relative > div.aspect-h-9 > img.object-cover
/r/talkstar-assets.s3.amazonaws.com/production/talks/talk...19.5 KiB6.0 KiB

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 1.0 s
URLTime Spent
ted.com/1.0 s
www.ted.com/0.0 ms

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 490 ms 49.8 KiB
URLTransfer SizeEst Savings
www.ted.com/_next/static/chunks/0jza3jk8q64jw.css51.1 KiB49.8 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTotal CPU TimeScript EvaluationScript Parse
Unattributable7.3 s275 ms0.0 ms
www.ted.com/_next/static/chunks/10ve7kro4jeja.js5.2 s3.3 s30 ms
www.ted.com/4.7 s77 ms11 ms
www.ted.com/_next/static/chunks/13mh4qsg0ojc3.js4.6 s300 ms13 ms
www.ted.com/_next/static/chunks/0.jna.w-3mqdg.js2.4 s1.7 s0.7 ms
cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano.js1.7 s1.5 s38 ms
www.ted.com/_next/static/chunks/0bokogfw9jzpb.js1.3 s862 ms3.5 ms
www.ted.com/_next/static/chunks/turbopack-0li4q.l8idl5g.js1.1 s1.1 s2.2 ms
media.begenuin.com/sdk/chunks/index-8EYXbSqT.js1.1 s807 ms8.2 ms
www.ted.com/_next/static/chunks/0-1uuud_vkogc.js950 ms192 ms25 ms
www.ted.com/_next/static/chunks/03ifowo1fb7pw.js941 ms418 ms6.7 ms
www.ted.com/_next/static/chunks/turbopack-0azua~rknfwv~.js814 ms770 ms2.1 ms
media.begenuin.com/sdk/chunks/vendor-external-O5cr870B.js789 ms539 ms2.1 ms
cdn.yourbow.com/ted/hbyb.js775 ms663 ms107 ms
cdn.fundraiseup.com/widget/AVFWZGUV535 ms445 ms55 ms
/pagead/managed/js/gpt/m202604130101/pubads_impl.js526 ms432 ms90 ms
www.ted.com/_next/static/chunks/0cvhe6ikgdp0s.js521 ms302 ms1.7 ms
static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js492 ms440 ms51 ms
static.cdn.prismic.io/prismic.js?new=true&repo=tedconf482 ms472 ms6.9 ms
www.ted.com/_next/static/chunks/0a6fv4704bgj..js477 ms332 ms2.2 ms
b-code.liadm.com/a-091g.min.js359 ms283 ms57 ms
static.fundraiseup.com/checkout.2fb913ca26161876.js292 ms4.1 ms287 ms
securepubads.g.doubleclick.net/tag/js/gpt.js285 ms189 ms25 ms
www.ted.com/_next/static/chunks/01cs1jed1svz9.js262 ms227 ms9.3 ms
www.ted.com/_next/static/chunks/0bmiy_96-93.m.js237 ms189 ms47 ms
ak.sail-horizon.com/spm/spm.v1.min.js174 ms134 ms34 ms
www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js171 ms43 ms13 ms
www.ted.com/_next/static/chunks/0jza3jk8q64jw.css164 ms0.0 ms0.0 ms
static.fundraiseup.com/elementsApi.6ed9e57bcd3c1e31.js148 ms126 ms20 ms
cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js147 ms66 ms19 ms
www.ted.com/_next/static/chunks/07zl3_penlz_s.js145 ms133 ms9.3 ms
www.ted.com/_next/static/chunks/0k~1425khwm0-.js120 ms114 ms1.8 ms
www.ted.com/_next/static/chunks/0hjo6tipsibej.js118 ms110 ms0.7 ms
www.ted.com/_next/static/chunks/0ix-kc_hcigst.js110 ms103 ms0.7 ms
www.ted.com/_next/static/chunks/0ohty3wb33a.t.js110 ms8.4 ms99 ms
www.ted.com/_next/static/chunks/0ho7~tksmakix.js105 ms99 ms0.8 ms
www.ted.com/_next/static/chunks/0f~to27mkl57p.js87 ms54 ms17 ms
media.begenuin.com/sdk/chunks/feed-C4rzC3fy.js87 ms7.2 ms7.1 ms
www.ted.com/_next/static/chunks/0b_a71hvct1_x.js76 ms73 ms2.2 ms
www.ted.com/_next/static/chunks/0t5s37rpo-ubb.js65 ms39 ms4.7 ms
www.ted.com/_next/static/chunks/0gn9txcop7as8.js62 ms48 ms7.0 ms
www.ted.com/_next/static/chunks/103m93trk0.3-.js60 ms50 ms0.7 ms
www.ted.com/_next/static/chunks/00a9rq1vyqi9..js60 ms5.0 ms53 ms
static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js58 ms1.9 ms55 ms
www.ted.com/_next/static/chunks/11fcdtdwh7wq2.js56 ms1.3 ms54 ms
www.ted.com/_next/static/chunks/0-l5m6uj81ywf.js55 ms30 ms22 ms
www.ted.com/_next/static/chunks/14m6_ev9cp687.js55 ms50 ms0.7 ms

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation17.8 s
Other13.9 s
Style & Layout5.6 s
Script Parsing & Compilation1.7 s
Rendering1.6 s
Garbage Collection491 ms
Parse HTML & CSS368 ms

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

More information about the performance of your application. These numbers don't directly affect the Performance score.

Layout shift culprits
Optimize DOM size
Font display
Modern HTTP
Render blocking requests
Optimize viewport for mobile
Minify CSS
User Timing marks and measures 16 user timings
Avoid long main-thread tasks 20 long tasks found
Avoid non-composited animations 1 animated element found
Image elements have explicit `width` and `height`
Page didn't prevent back/forward cache restoration
Network Requests
Network Round Trip Times 100 ms
Server Backend Latencies 140 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Initial server response time was short Root document took 0 ms
Avoid large layout shifts 2 layout shifts found
INP breakdown
76

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

ARIA

ARIA dialog elements without accessible names may prevent screen readers users from discerning the purpose of these elements. Learn how to make ARIA dialog elements more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
A challenge for your brain Daily word, logic, and strategy games that push your… body.antialiased > section#sailthru-overlay-container

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#hero-slider-images > div.cloned-standard-hero-slider-nav-prev > div.absolute > button.group div#hero-slider-images > div.cloned-standard-hero-slider-nav-prev > div.absolute > button.group
div#hero-slider-images > div.cloned-standard-hero-slider-nav-next > div.absolute > button.group div#hero-slider-images > div.cloned-standard-hero-slider-nav-next > div.absolute > button.group
div.gencl:absolute > div.gencl:absolute > div.gencl:flex > button.gencl:inline-flex div.gencl:absolute > div.gencl:absolute > div.gencl:flex > button.gencl:inline-flex
div.gencl:absolute > div.gencl:absolute > div.gencl:flex > button.gencl:inline-flex div.gencl:absolute > div.gencl:absolute > div.gencl:flex > button.gencl:inline-flex
div.gencl:absolute > div.gencl:absolute > div.gencl:flex > button.gencl:inline-flex div.gencl:absolute > div.gencl:absolute > div.gencl:flex > button.gencl:inline-flex
body.antialiased > section#sailthru-overlay-container > div.sailthru-overlay > button.sailthru-overlay-close body.antialiased > section#sailthru-overlay-container > div.sailthru-overlay > button.sailthru-overlay-close

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.flex > div.mb-8 > div.relative > input.newsletter-input div.flex > div.mb-8 > div.relative > input.newsletter-input

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.mx-auto > div.flex > div.h-100 > a div.mx-auto > div.flex > div.h-100 > a
div.mx-auto > div.flex > div.h-100 > a div.mx-auto > div.flex > div.h-100 > a
div.w-full > div > div.mb-2 > a.relative div.w-full > div > div.mb-2 > a.relative
div.w-full > div > div.mb-2 > a.relative div.w-full > div > div.mb-2 > a.relative
div.w-full > div > div.mb-2 > a.relative div.w-full > div > div.mb-2 > a.relative

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
head > meta head > meta

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Storage Preferences div#befbc0e5-ee15-4e14-8ba1-c77e210294a9 > div.osano-cm-dialog__content > p.osano-cm-content__drawer-links > a.osano-cm-drawer-links__link
Third Parties div#befbc0e5-ee15-4e14-8ba1-c77e210294a9 > div.osano-cm-dialog__content > p.osano-cm-content__drawer-links > a.osano-cm-drawer-links__link
LOVE div.flex > div.flex > div.flex > a.relative
SCIENCE div.flex > div.flex > div.flex > a.relative
BUSINESS div.flex > div.flex > div.flex > a.relative
TECHNOLOGY div.flex > div.flex > div.flex > a.relative
RELATIONSHIPS div.flex > div.flex > div.flex > a.relative
RELATIONSHIPS div.flex > div.flex > div.flex > a.relative
HEALTH div.flex > div.grid > div.flex > a.relative
WAR div.flex > div.grid > div.flex > a.relative
SCIENCE div.flex > div.grid > div.flex > a.relative
TECHNOLOGY div.flex > div.grid > div.flex > a.relative
GLOBAL ISSUES div.flex > div.grid > div.flex > a.relative
TECHNOLOGY div.flex > div.grid > div.flex > a.relative

These items highlight common accessibility best practices.

Interactive controls are keyboard focusable
Interactive elements indicate their purpose and state
The page has a logical tab order
Visual order on the page follows DOM order
User focus is not accidentally trapped in a region
The user's focus is directed to new content added to the page
HTML5 landmark elements are used to improve navigation
Offscreen content is hidden from assistive technology
Custom controls have associated labels
Custom controls have ARIA roles
`[aria-*]` attributes match their roles
`[aria-hidden="true"]` is not present on the document `<body>`
`[role]`s have all required `[aria-*]` attributes
`[role]` values are valid
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
Image elements have `[alt]` attributes
ARIA attributes are used as specified for the element's role
`[aria-hidden="true"]` elements do not contain focusable descendents
Elements use only permitted ARIA attributes
Background and foreground colors have a sufficient contrast ratio
Document has a `<title>` element
`<frame>` or `<iframe>` elements have a title
`<html>` element has a `[lang]` attribute
`<html>` element has a valid value for its `[lang]` attribute
Links are distinguishable without relying on color.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
No element has a `[tabindex]` value greater than 0
Heading elements appear in a sequentially-descending order
Document has a main landmark.
Deprecated ARIA roles were not used
`<video>` elements contain a `<track>` element with `[kind="captions"]`
Identical links have the same purpose.
`[accesskey]` values are unique
`button`, `link`, and `menuitem` elements have accessible names
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
`[role]`s are contained by their required parent element
Elements with the `role=text` attribute do not have focusable descendents.
ARIA toggle fields have accessible names
ARIA `tooltip` elements have accessible names
ARIA `treeitem` elements have accessible names
The page contains a heading, skip link, or landmark region
`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Definition list items are wrapped in `<dl>` elements
ARIA IDs are unique
No form fields have multiple labels
`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
Input buttons have discernible text.
`<input type="image">` elements have `[alt]` text
The document does not use `<meta http-equiv="refresh">`
`<object>` elements have alternate text
Select elements have associated label elements.
Skip links are focusable.
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
`[lang]` attributes have a valid value
Tables have different content in the summary attribute and `<caption>`.
All heading elements contain content.
Uses ARIA roles only on compatible elements
Image elements do not have `[alt]` attributes that are redundant text.
Elements with visible text labels have matching accessible names.
Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
`<td>` elements in a large `<table>` have one or more table headers.
96

Best Practices

General

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
[CMP Monitor] Osano failure: timeout Osano did not initialize within 2000ms
Uses HTTPS
Avoids deprecated APIs
Avoids third-party cookies
Allows users to paste into input fields
Avoids requesting the geolocation permission on page load
Avoids requesting the notification permission on page load
Displays images with correct aspect ratio
Serves images with appropriate resolution
Page has the HTML doctype
Properly defines charset
No issues in the `Issues` panel in Chrome Devtools
Ensure CSP is effective against XSS attacks
Use a strong HSTS policy
Ensure proper origin isolation with COOP
Mitigate DOM-based XSS with Trusted Types
Detected JavaScript libraries
Page has valid source maps
Redirects HTTP traffic to HTTPS
Mitigate clickjacking with XFO or CSP
100

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Structured data is valid
Page isn’t blocked from indexing
Document has a `<title>` element
Document has a meta description
Page has successful HTTP status code
Links have descriptive text
Links are crawlable
robots.txt is valid
Image elements have `[alt]` attributes
Document has a valid `hreflang`
Document has a valid `rel=canonical`

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

39
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
77
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.19 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

3.58 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

1.36 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.017

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

4.78 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

7.58 s

Detailed Report

Audit breakdown by category with detailed findings.

39

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:230.336 source:map[column:137515 line:1 type:source-location url:https://www.ted.com/_next/static/chunks/10ve7kro4jeja.js urlProvider:network]]]
headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:139.9 source:map[type:text value:[unattributed]]] map[reflowTime:113.688 source:map[column:4871 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:110.214 source:map[column:26857 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:3.887 source:map[column:33340 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:2.547 source:map[column:27358 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:105.709 source:map[column:20327 line:0 type:source-location url:https://www.ted.com/_next/static/chunks/0ez-x3h3dxkrv.js urlProvider:network]] map[reflowTime:4.239 source:map[column:30031 line:1 type:source-location url:https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js urlProvider:network]] map[reflowTime:4.176 source:map[column:62355 line:1 type:source-location url:https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js urlProvider:network]] map[reflowTime:0.994 source:map[column:62714 line:1 type:source-location url:https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano-ui.js urlProvider:network]] map[reflowTime:1.318 source:map[column:237223 line:18 type:source-location url:https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604130101/pubads_impl.js urlProvider:network]]]

Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:label label:Subpart valueType:text] map[key:duration label:Duration valueType:ms]]
items: [map[duration:337.615 label:Time to first byte subpart:timeToFirstByte] map[duration:2057.075 label:Resource load delay subpart:resourceLoadDelay] map[duration:71.152 label:Resource load duration subpart:resourceLoadDuration] map[duration:413.783 label:Element render delay subpart:elementRenderDelay]]
lhId: page-0-IMG
nodeLabel: Promo image
path: 1,HTML,1,BODY,1,DIV,1,DIV,1,DIV,1,MAIN,0,DIV,1,SECTION,0,DIV,0,DIV,0,DIV,1,A,0,DIV,0,DIV,0,IMG
selector: a.relative > div.relative > div.aspect-h-9 > img.object-cover
snippet: <img alt="Promo image" loading="lazy" decoding="async" data-nimg="fill" class="object-cover" sizes="(min-width: 1200px) 580px, 50vw" srcset="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad0nCZ1ZCF7ETJbs_TEDLive…" src="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad0nCZ1ZCF7ETJbs_TEDLive…" style="position: absolute; height: 100%; width: 100%; inset: 0px;">

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-IMG
nodeLabel: Promo image
path: 1,HTML,1,BODY,1,DIV,1,DIV,1,DIV,1,MAIN,0,DIV,1,SECTION,0,DIV,0,DIV,0,DIV,1,A,0,DIV,0,DIV,0,IMG
selector: a.relative > div.relative > div.aspect-h-9 > img.object-cover
snippet: <img alt="Promo image" loading="lazy" decoding="async" data-nimg="fill" class="object-cover" sizes="(min-width: 1200px) 580px, 50vw" srcset="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad0nCZ1ZCF7ETJbs_TEDLive…" src="https://pi.tedcdn.com/r/images.prismic.io/tedconf/ad0nCZ1ZCF7ETJbs_TEDLive…" style="position: absolute; height: 100%; width: 100%; inset: 0px;">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

More than 4 preconnect connections were found. These should be used sparingly and only to the most important origins.
description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
ak.sail-horizon.com/spm/spm.v1.min.js48.1 KiB319 ms

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
Promo image a.relative > div.relative > div.aspect-h-9 > img.object-cover
/r/images.prismic.io/tedconf/ad0nCZ1ZCF7ETJbs_TEDLivehome...227.4 KiB196.6 KiB
Why friendship can be just as meaningful as romantic love div.flex > a.relative > div.relative > img.rounded-xs
/r/talkstar-assets.s3.amazonaws.com/production/talks/talk...195.8 KiB183.1 KiB
amen_ra_mashariki_and_manoush_zomorodi_how_to_make_ai_a_force_for_good_in_clima… a.relative > div.relative > div.aspect-h-9 > img.object-cover
/r/talkstar-assets.s3.amazonaws.com/production/talks/talk...288.6 KiB175.9 KiB
How to calm your anxiety, from a neuroscientist div.flex > a.relative > div.relative > img.rounded-xs
/r/talkstar-photos.s3.amazonaws.com/uploads/86911e2c-5019...116.5 KiB112.3 KiB
niko_zlotnik_how_do_snakes_swallow_animals_so_much_bigger_than_they_are a.relative > div.relative > div.aspect-h-9 > img.object-cover
/r/talkstar-assets.s3.amazonaws.com/production/talks/talk...110.7 KiB67.5 KiB
div.flex > div.h-100 > a > img div.flex > div.h-100 > a > img
/r/images.prismic.io/tedconf/aZ97IMFoBIGEg04j_T26_Members...89.8 KiB50.8 KiB
ted_idea_search_buenos_aires_argentina a.relative > div.relative > div.aspect-h-9 > img.object-cover
/r/talkstar-assets.s3.amazonaws.com/production/talks/talk...19.5 KiB6.0 KiB

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 483 ms
URLTime Spent
ted.com/483 ms
www.ted.com/0.0 ms

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 40 ms 48.9 KiB
URLTransfer SizeEst Savings
www.ted.com/_next/static/chunks/0jza3jk8q64jw.css51.1 KiB48.9 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation3.7 s
Other1.7 s
Style & Layout1.1 s
Script Parsing & Compilation423 ms
Rendering306 ms
Garbage Collection99 ms
Parse HTML & CSS90 ms

More information about the performance of your application. These numbers don't directly affect the Performance score.

Layout shift culprits
Optimize DOM size
Font display
Modern HTTP
Optimize viewport for mobile
Minify CSS
Minify JavaScript
User Timing marks and measures 16 user timings
Avoid long main-thread tasks 20 long tasks found
Image elements have explicit `width` and `height`
Page didn't prevent back/forward cache restoration
Network Requests
Network Round Trip Times 90 ms
Server Backend Latencies 150 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Initial server response time was short Root document took 0 ms
Avoid large layout shifts 4 layout shifts found
INP breakdown
Avoid non-composited animations
77

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.relative > div.z-50 > div.absolute > button.group div.relative > div.z-50 > div.absolute > button.group

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.flex > div.mb-8 > div.relative > input.newsletter-input div.flex > div.mb-8 > div.relative > input.newsletter-input

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.mx-auto > div.flex > div.h-100 > a div.mx-auto > div.flex > div.h-100 > a
div.mx-auto > div.flex > div.h-100 > a div.mx-auto > div.flex > div.h-100 > a
div.w-full > div > div.mb-2 > a.relative div.w-full > div > div.mb-2 > a.relative
div.w-full > div > div.mb-2 > a.relative div.w-full > div > div.mb-2 > a.relative
div.w-full > div > div.mb-2 > a.relative div.w-full > div > div.mb-2 > a.relative

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
HEALTH div.grid > div.flex > a.relative > p.text-textPrimary-onLight
Irena Arslanova · 496K plays · 1 year ago div.flex > div.grid > a.pr-5 > p.pt-2
WAR div.grid > div.flex > a.relative > p.text-textPrimary-onLight
Bel Trew · 483K plays · 2 years ago div.flex > div.grid > a.pr-5 > p.pt-2
SCIENCE div.grid > div.flex > a.relative > p.text-textPrimary-onLight
Tara Boroushaki · 659K plays · 2 years ago div.flex > div.grid > a.pr-5 > p.pt-2
TECHNOLOGY div.grid > div.flex > a.relative > p.text-textPrimary-onLight
Ordinary Things · 1.41M plays · 3 years ago div.flex > div.grid > a.pr-5 > p.pt-2
GLOBAL ISSUES div.grid > div.flex > a.relative > p.text-textPrimary-onLight
Priscilla Chomba-Kinywa · 2.08M plays · 4 years ago div.flex > div.grid > a.pr-5 > p.pt-2
TECHNOLOGY div.grid > div.flex > a.relative > p.text-textPrimary-onLight
Eric Hinterman · 1.71M plays · 4 years ago div.flex > div.grid > a.pr-5 > p.pt-2

These are opportunities to improve the legibility of your content.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
head > meta head > meta

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Storage Preferences div#3a772abe-8b25-4742-973b-90527a9b1a55 > div.osano-cm-dialog__content > p.osano-cm-content__drawer-links > a.osano-cm-drawer-links__link
Third Parties div#3a772abe-8b25-4742-973b-90527a9b1a55 > div.osano-cm-dialog__content > p.osano-cm-content__drawer-links > a.osano-cm-drawer-links__link
GET YOUR PASS div.mx-auto > div.grid > div.flex > a.relative
LOVE div.flex > div.flex > div.flex > a.relative
SCIENCE div.flex > div.flex > div.flex > a.relative
BUSINESS div.flex > div.flex > div.flex > a.relative
TECHNOLOGY div.flex > div.flex > div.flex > a.relative
RELATIONSHIPS div.flex > div.flex > div.flex > a.relative
HEALTH div.flex > div.grid > div.flex > a.relative
WAR div.flex > div.grid > div.flex > a.relative
SCIENCE div.flex > div.grid > div.flex > a.relative
TECHNOLOGY div.flex > div.grid > div.flex > a.relative
GLOBAL ISSUES div.flex > div.grid > div.flex > a.relative
TECHNOLOGY div.flex > div.grid > div.flex > a.relative

These items highlight common accessibility best practices.

Interactive controls are keyboard focusable
Interactive elements indicate their purpose and state
The page has a logical tab order
Visual order on the page follows DOM order
User focus is not accidentally trapped in a region
The user's focus is directed to new content added to the page
HTML5 landmark elements are used to improve navigation
Offscreen content is hidden from assistive technology
Custom controls have associated labels
Custom controls have ARIA roles
`[aria-*]` attributes match their roles
`[aria-hidden="true"]` is not present on the document `<body>`
`[role]`s have all required `[aria-*]` attributes
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
`[role]` values are valid
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
Image elements have `[alt]` attributes
ARIA attributes are used as specified for the element's role
Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
`[aria-hidden="true"]` elements do not contain focusable descendents
Elements use only permitted ARIA attributes
Document has a `<title>` element
`<frame>` or `<iframe>` elements have a title
`<html>` element has a `[lang]` attribute
`<html>` element has a valid value for its `[lang]` attribute
Links are distinguishable without relying on color.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
No element has a `[tabindex]` value greater than 0
Heading elements appear in a sequentially-descending order
Document has a main landmark.
Deprecated ARIA roles were not used
Identical links have the same purpose.
Elements with visible text labels have matching accessible names.
`[accesskey]` values are unique
`button`, `link`, and `menuitem` elements have accessible names
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
`[role]`s are contained by their required parent element
Elements with the `role=text` attribute do not have focusable descendents.
ARIA toggle fields have accessible names
ARIA `tooltip` elements have accessible names
ARIA `treeitem` elements have accessible names
The page contains a heading, skip link, or landmark region
`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Definition list items are wrapped in `<dl>` elements
ARIA IDs are unique
No form fields have multiple labels
`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
Input buttons have discernible text.
`<input type="image">` elements have `[alt]` text
The document does not use `<meta http-equiv="refresh">`
`<object>` elements have alternate text
Select elements have associated label elements.
Skip links are focusable.
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
`[lang]` attributes have a valid value
`<video>` elements contain a `<track>` element with `[kind="captions"]`
Tables have different content in the summary attribute and `<caption>`.
All heading elements contain content.
Uses ARIA roles only on compatible elements
Image elements do not have `[alt]` attributes that are redundant text.
Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
`<td>` elements in a large `<table>` have one or more table headers.
96

Best Practices

General

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
www.ted.com/ line 33, col 24
[CMP Monitor] Osano failure: timeout Osano did not initialize within 2000ms
Uses HTTPS
Avoids deprecated APIs
Avoids third-party cookies
Allows users to paste into input fields
Avoids requesting the geolocation permission on page load
Avoids requesting the notification permission on page load
Displays images with correct aspect ratio
Serves images with appropriate resolution
Page has the HTML doctype
Properly defines charset
No issues in the `Issues` panel in Chrome Devtools
Ensure CSP is effective against XSS attacks
Use a strong HSTS policy
Ensure proper origin isolation with COOP
Mitigate DOM-based XSS with Trusted Types
Detected JavaScript libraries
Page has valid source maps
Redirects HTTP traffic to HTTPS
Mitigate clickjacking with XFO or CSP
100

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Structured data is valid
Page isn’t blocked from indexing
Document has a `<title>` element
Document has a meta description
Page has successful HTTP status code
Links have descriptive text
Links are crawlable
robots.txt is valid
Image elements have `[alt]` attributes
Document has a valid `hreflang`
Document has a valid `rel=canonical`

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