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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
25
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
80
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
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.

5.18 s

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

13.68 s

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

8.06 s

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

0.059

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

18.86 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.

40.04 s

Page Load Progression

1.3 s
2.7 s
4.0 s
5.4 s
6.7 s
8.1 s
9.4 s
10.7 s
Checks
14
5 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
26.4 MB transferred, 295 requests
FIX
26.4 MB transferred, 295 requests
Critical::
Page weighs 39.4 MB (26.4 MB transferred)
Warning::
Images are 4.5 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 4.5 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::
295 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 5.5 g CO2 per page load
26.4 MB / 2.4 MB budget
26.4 MB transferred
295 requests
5.5 g CO2 per page load
Other 16.9 MiB 64%
Images 4.5 MiB 17%
JavaScript 3.6 MiB 14%
Other 735.8 KiB 3%
Fonts 434.6 KiB 2%
HTML 132.7 KiB 0%
CSS 91.8 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 (24.5 MiB of 26.4 MiB)
Info::
Third-party blocking time is low (0 ms)
93%
First-party Third-party
F
JS Execution Cost
Action
31081ms total JS execution
FIX
31081ms total JS execution
Warning::
Unattributable: 6065ms CPU time
Warning::
https://www.ted.com/_next/static/chunks/0ujyvbd_j_...: 4606ms CPU time
Warning::
https://www.ted.com/_next/static/chunks/0ceke3n72t...: 4114ms CPU time
Warning::
https://www.ted.com/: 3487ms CPU time
Warning::
https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-f...: 1795ms CPU time
Info::
Third-party scripts: 12369ms (40% of total)

Main Thread Breakdown

Script Evaluation 39% Other 37% Style & Layout 14% Script Parsing & Compilation 4% Rendering 4%
ScriptTotalScriptingParse/CompileParty
Unattributable6065ms213ms0ms3rd
https://www.ted.com/_next/static/chunks/0ujyvbd_j_-yn.js4606ms310ms10ms1st
https://www.ted.com/_next/static/chunks/0ceke3n72t5kx.js4114ms2449ms26ms1st
https://www.ted.com/3487ms81ms8ms1st
https://cmp.osano.com/AzqTgHUHUGJa7gInt/9e4d9097-fa02-474b-9ac9-958cf3f54337/osano.js1795ms1294ms30ms3rd
https://www.ted.com/_next/static/chunks/0.jna.w-3mqdg.js1569ms1113ms0ms1st
https://www.ted.com/_next/static/chunks/turbopack-0wz1ql9lnw2yx.js891ms884ms2ms1st
https://www.ted.com/_next/static/chunks/0g32t8vp0x1r6.js856ms549ms2ms1st
https://media.begenuin.com/sdk/chunks/index-8EYXbSqT.js851ms603ms7ms3rd
https://media.begenuin.com/sdk/chunks/vendor-external-O5cr870B.js722ms468ms2ms3rd

Showing top 10 of 38 scripts

F
JS Bundles
Action
127 scripts, 1.8 MB unused
FIX
127 scripts, 1.8 MB unused
Warning::
https://static.fundraiseup.com/checkout.098fc4d30f...: 354 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 (88%)
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...: 160 KB unused (56%)
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://cdn.yourbow.com/ted/hbyb.js: 140 KB unused (71%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://securepubads.g.doubleclick.net/pagead/mana...: 126 KB unused (69%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.8 MB
1812 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://static.fundraiseup.com/checkout.098fc4d30f8503a0.js397 KB354 KB (89%)✓3rd
https://media.begenuin.com/sdk/chunks/feed-C4rzC3fy.js196 KB172 KB (88%)✗3rd
https://media.begenuin.com/sdk/chunks/index-8EYXbSqT.js287 KB160 KB (56%)✗3rd
https://cdn.yourbow.com/ted/hbyb.js196 KB140 KB (71%)✓3rd
https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202603310101/pubads_impl.js182 KB126 KB (69%)✓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 KB99 KB (76%)✗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
33 images, 0 KB saveable
REVIEW
33 images, 0 KB saveable
Info::
All images are well-optimized
33 images 4.5 MB
0 oversized -0 KB
26 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 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s FCP 5.2 s LCP 13.7 shttps://www.ted.com/assets/fonts/ted-ui-icons.ttf?ii9i6eted-ui-icons.ttf https://www.ted.com/assets/fonts/ted-ui-icons.ttf?ii9i6e — 18.5 KiB — 0 ms — font-display: swaphttps://pl.tedcdn.com/fonts/InterVariable.woff2InterVariable.woff2 https://pl.tedcdn.com/fonts/InterVariable.woff2 — 344.6 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
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
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
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
21 hints, 0 missing preconnects
PASS
21 hints, 0 missing preconnects
Info::
Page uses 21 resource hint(s)

Current Resource Hints

preconnect
+2
12
preload
4
dns-prefetch
1
prefetch
4

21 resource hints configured

Network Waterfall
295 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
40% of JavaScript execution is third-party
First-party Third-party 12369ms · 1587KB · €134/mo
Unattributable
Other
Costly
Execution 6065ms
Transfer 0 KB
Monthly Cost €66/mo
cmp.osano.com
Other
Costly
Execution 1795ms
Transfer 59 KB
Monthly Cost €19/mo
media.begenuin.com
Other
Costly
Execution 851ms
Transfer 287 KB
Unused 56%
Monthly Cost €9/mo
media.begenuin.com
Other
Costly
Execution 722ms
Transfer 76 KB
Unused 36%
Monthly Cost €8/mo
cdn.yourbow.com
Other
Costly
Execution 551ms
Transfer 196 KB
Unused 71%
Monthly Cost €6/mo
securepubads.g.doubleclick.net
Other
Costly
Execution 467ms
Transfer 182 KB
Unused 69%
Monthly Cost €5/mo
static.fundraiseup.com
Other
Costly
Execution 363ms
Transfer 105 KB
Unused 83%
Monthly Cost €4/mo
cdn.fundraiseup.com
Other
Costly
Execution 336ms
Transfer 70 KB
Unused 38%
Monthly Cost €4/mo
static.fundraiseup.com
Other
Costly
Execution 279ms
Transfer 397 KB
Unused 89%
Monthly Cost €3/mo
static.cdn.prismic.io
Other
Costly
Execution 274ms
Transfer 10 KB
Monthly Cost €3/mo
ak.sail-horizon.com
Other
Costly
Execution 202ms
Transfer 55 KB
Unused 60%
Monthly Cost €2/mo
securepubads.g.doubleclick.net
Other
Optional
Execution 139ms
Transfer 34 KB
Monthly Cost €2/mo
static.fundraiseup.com
Other
Optional
Execution 127ms
Transfer 37 KB
Unused 55%
Monthly Cost €1/mo
b-code.liadm.com
Other
Optional
Execution 112ms
Transfer 47 KB
Unused 47%
Monthly Cost €1/mo
cmp.osano.com
Other
Optional
Execution 84ms
Transfer 31 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 6065ms and costs ~€66/month
  • cmp.osano.com adds 1795ms and costs ~€19/month
  • media.begenuin.com adds 851ms and costs ~€9/month
  • media.begenuin.com adds 722ms and costs ~€8/month
  • cdn.yourbow.com adds 551ms and costs ~€6/month
  • securepubads.g.doubleclick.net adds 467ms and costs ~€5/month
  • static.fundraiseup.com adds 363ms and costs ~€4/month
  • cdn.fundraiseup.com adds 336ms and costs ~€4/month
  • static.fundraiseup.com adds 279ms and costs ~€3/month
  • static.cdn.prismic.io adds 274ms and costs ~€3/month
  • ak.sail-horizon.com adds 202ms and costs ~€2/month

Unattributable takes 6065ms 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 1795ms 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

media.begenuin.com takes 851ms 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

56% 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

media.begenuin.com takes 722ms 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

cdn.yourbow.com takes 551ms 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

71% of cdn.yourbow.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

securepubads.g.doubleclick.net takes 467ms 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

69% 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

static.fundraiseup.com takes 363ms 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

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

cdn.fundraiseup.com takes 336ms 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

static.fundraiseup.com takes 279ms 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

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

static.cdn.prismic.io takes 274ms 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

ak.sail-horizon.com takes 202ms 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

60% of ak.sail-horizon.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

55% 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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