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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
64
GRADE
D
FIX
4
REVIEW
3
PASS
5
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
44
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.
77
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.

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

918 ms

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

3.28 s

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

1.04 s

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

0.026

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

3.57 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.

8.59 s

Page Load Progression

439 ms
878 ms
1.3 s
1.8 s
2.2 s
2.6 s
3.1 s
3.5 s
Checks
14
5 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
27.4 MB transferred, 299 requests
FIX
27.4 MB transferred, 299 requests
Critical::
Page weighs 40.8 MB (27.4 MB transferred)
Warning::
Images are 5.2 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 5.2 MB
Warning::
JavaScript is 3.6 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 3.6 MB
Info::
Fonts are 435 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 435 KB
Warning::
299 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 5.7 g CO2 per page load
27.4 MB / 2.4 MB budget
27.4 MB transferred
299 requests
5.7 g CO2 per page load
Other 17.1 MiB 62%
Images 5.2 MiB 19%
JavaScript 3.6 MiB 13%
Other 854.7 KiB 3%
Fonts 434.7 KiB 2%
HTML 132.7 KiB 0%
CSS 91.7 KiB 0%
Other 26.1 KiB 0%
Other 21.1 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

D
Third-Party Impact
Action
93% third-party, 0 ms blocking
FIX
93% third-party, 0 ms blocking
Warning::
Third-party code accounts for 93% of page weight (25.4 MiB of 27.4 MiB)
Info::
Third-party blocking time is low (0 ms)
93%
First-party Third-party
F
JS Execution Cost
Action
7137ms total JS execution
FIX
7137ms total JS execution
Warning::
Unattributable: 1895ms CPU time
Warning::
https://www.ted.com/_next/static/chunks/0ceke3n72t...: 947ms CPU time
Warning::
https://www.ted.com/: 906ms CPU time
Warning::
https://www.ted.com/_next/static/chunks/0ujyvbd_j_...: 631ms CPU time
Warning::
https://www.ted.com/_next/static/chunks/0.jna.w-3m...: 377ms CPU time
Info::
Third-party scripts: 3143ms (44% of total)

Main Thread Breakdown

Script Evaluation 39% Other 37% Style & Layout 14% Script Parsing & Compilation 4%
ScriptTotalScriptingParse/CompileParty
Unattributable1895ms50ms0ms3rd
https://www.ted.com/_next/static/chunks/0ceke3n72t5kx.js947ms624ms6ms1st
https://www.ted.com/906ms12ms2ms1st
https://www.ted.com/_next/static/chunks/0ujyvbd_j_-yn.js631ms47ms3ms1st
https://www.ted.com/_next/static/chunks/0.jna.w-3mqdg.js377ms270ms0ms1st
https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano.js317ms291ms7ms3rd
https://www.ted.com/_next/static/chunks/turbopack-0wz1ql9lnw2yx.js193ms192ms0ms1st
https://www.ted.com/_next/static/chunks/turbopack-0ij34tcl~3kf8.js162ms147ms0ms1st
https://www.ted.com/_next/static/chunks/146slgz6dfxmj.js155ms57ms1ms1st
https://www.ted.com/_next/static/chunks/0ku8i~ce5wfyc.js155ms54ms2ms1st

Showing top 10 of 23 scripts

F
JS Bundles
Action
128 scripts, 1.7 MB unused
FIX
128 scripts, 1.7 MB unused
Warning::
https://static.fundraiseup.com/checkout.098fc4d30f...: 355 KB unused (89%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://media.begenuin.com/sdk/chunks/feed-C4rzC3f...: 172 KB unused (89%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://media.begenuin.com/sdk/chunks/feed-C4rzC3f...: unminified — 68 KB could be saved
Warning::
https://media.begenuin.com/sdk/chunks/index-8EYXbS...: 164 KB unused (57%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://media.begenuin.com/sdk/chunks/index-8EYXbS...: unminified — 97 KB could be saved
Warning::
https://securepubads.g.doubleclick.net/pagead/mana...: 123 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://media.begenuin.com/sdk/chunks/vendor-forms...: 119 KB unused (75%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.7 MB
1773 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://static.fundraiseup.com/checkout.098fc4d30f8503a0.js398 KB355 KB (89%)✓3rd
https://media.begenuin.com/sdk/chunks/feed-C4rzC3fy.js196 KB172 KB (89%)✗3rd
https://media.begenuin.com/sdk/chunks/index-8EYXbSqT.js287 KB164 KB (57%)✗3rd
https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604010101/pubads_impl.js?cb=31097617182 KB123 KB (68%)✓3rd
https://media.begenuin.com/sdk/chunks/vendor-forms-BRAWdd6O.js160 KB119 KB (75%)✗3rd
https://static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js112 KB112 KB (100%)✓3rd
https://media.begenuin.com/sdk/chunks/vendor-animation-Cov7gVAf.js131 KB100 KB (76%)✗3rd
https://cdn.yourbow.com/ted/hbyb.js196 KB91 KB (47%)✓3rd
https://static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js105 KB87 KB (83%)✓3rd
https://www.ted.com/_next/static/chunks/03515l8a52213.js84 KB62 KB (74%)✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

B
Image Optimization
35 images, 0 KB saveable
REVIEW
35 images, 0 KB saveable
Info::
All images are well-optimized
35 images 5.2 MB
0 oversized -0 KB
34 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
s-maxage=180, stale-while-revalidate=31535820
REVIEW
s-maxage=180, stale-while-revalidate=31535820
Info::
Cache-Control header is set
Got: s-maxage=180, stale-while-revalidate=31535820
Info::
CDN TTL: 3 minutes (s-maxage=180)
Info::
ETag present — enables conditional (304) responses
Cache-Control

s-maxage=180, stale-while-revalidate=31535820

DirectiveValueMeaning
s-maxage180CDN caches for 3 minutes
stale-while-revalidate31535820Serve stale for 52 weeks while fetching fresh
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
3 fonts (435 KB)
PASS
3 fonts (435 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

435 KB total

Render-blocking

0

of 3

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s FCP 918 ms LCP 3.3 shttps://pl.tedcdn.com/fonts/InterVariable.woff2InterVariable.woff2 https://pl.tedcdn.com/fonts/InterVariable.woff2 — 344.6 KiB — 0 ms — font-display: swaphttps://www.ted.com/assets/fonts/ted-ui-icons.ttf?ii9i6eted-ui-icons.ttf https://www.ted.com/assets/fonts/ted-ui-icons.ttf?ii9i6e — 18.6 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/inter/v18/UcCo3FwrK3iLTcviYwYZ8UA3.woff2UcCo3FwrK3iLTcviYwYZ8UA... https://fonts.gstatic.com/s/inter/v18/UcCo3FwrK3iLTcviYwYZ8UA3.woff2 — 71.4 KiB — 0 ms — font-display: swap
InterVariable.woff2 woff2 swap
Size 345 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
ted-ui-icons.ttf ttf swap
Size 19 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
UcCo3FwrK3iLTcviYwYZ8UA... woff2 swap
Size 71 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)

Fixing the unchecked items could save ~178 KB and ~356 ms

A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
299 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
44% of JavaScript execution is third-party
First-party Third-party 3143ms · 1383KB · €34/mo
Unattributable
Other
Costly
Execution 1895ms
Transfer 0 KB
Monthly Cost €21/mo
cmp.osano.com
Other
Costly
Execution 317ms
Transfer 59 KB
Monthly Cost €3/mo
media.begenuin.com
Other
Optional
Execution 153ms
Transfer 76 KB
Unused 36%
Monthly Cost €2/mo
securepubads.g.doubleclick.net
Other
Optional
Execution 152ms
Transfer 182 KB
Unused 68%
Monthly Cost €2/mo
cdn.yourbow.com
Other
Optional
Execution 149ms
Transfer 196 KB
Unused 47%
Monthly Cost €2/mo
media.begenuin.com
Other
Optional
Execution 140ms
Transfer 287 KB
Unused 57%
Monthly Cost €2/mo
cdn.fundraiseup.com
Other
Optional
Execution 107ms
Transfer 69 KB
Unused 38%
Monthly Cost €1/mo
static.fundraiseup.com
Other
Optional
Execution 104ms
Transfer 105 KB
Unused 83%
Monthly Cost €1/mo
static.cdn.prismic.io
Other
Optional
Execution 65ms
Transfer 10 KB
Monthly Cost €1/mo
static.fundraiseup.com
Other
Optional
Execution 62ms
Transfer 398 KB
Unused 89%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 1895ms and costs ~€21/month
  • cmp.osano.com adds 317ms and costs ~€3/month

44% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

Unattributable takes 1895ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

cmp.osano.com takes 317ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

68% of securepubads.g.doubleclick.net's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

57% of media.begenuin.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

83% of static.fundraiseup.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

89% of static.fundraiseup.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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