Skip to content
https://www.openai.com

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
74
GRADE
C
FIX
5
REVIEW
0
PASS
9
INFO
2

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

Mobile Desktop
37
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
81
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.

2.37 s

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

23.11 s

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

2.00 s

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

0.000

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

7.38 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.

23.48 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
16
9 PASS 5 FIX
F
Page Weight Budget
Action
3.8 MB transferred, 103 requests
FIX
3.8 MB transferred, 103 requests
Warning::
Page weighs 14.6 MB (3.8 MB transferred)
Warning::
JavaScript is 3.2 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 3.2 MB
Warning::
103 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.81 g CO2 per page load
3.8 MB / 2.4 MB budget
3.8 MB transferred
103 requests
0.81 g CO2 per page load
JavaScript 3.2 MiB 82%
Other 254.9 KiB 6%
Images 179.7 KiB 5%
Fonts 148.2 KiB 4%
CSS 67.2 KiB 2%
HTML 41.4 KiB 1%
Other 2.9 KiB 0%
Other 1.1 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

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

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
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (3.8 MiB of 3.8 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
5462ms total JS execution
FIX
5462ms total JS execution
Warning::
https://openai.com/_next/static/chunks/17656-df86b...: 1072ms CPU time
Warning::
https://openai.com/_next/static/chunks/72002-2f6e1...: 988ms CPU time
Warning::
Unattributable: 953ms CPU time
Warning::
https://openai.com/: 772ms CPU time
Warning::
https://openai.com/_next/static/chunks/59287-44095...: 746ms CPU time
Warning::
Third-party scripts: 5462ms (100% of total)

Main Thread Breakdown

Script Evaluation 56% Script Parsing & Compilation 17% Other 15% Style & Layout 8%
ScriptTotalScriptingParse/CompileParty
https://openai.com/_next/static/chunks/17656-df86be67c68c878e.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f631072ms964ms105ms3rd
https://openai.com/_next/static/chunks/72002-2f6e1dde422f088e.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63988ms860ms19ms3rd
Unattributable953ms179ms0ms3rd
https://openai.com/772ms64ms51ms3rd
https://openai.com/_next/static/chunks/59287-440951e0a38e8486.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63746ms734ms3ms3rd
https://openai.com/cdn-cgi/challenge-platform/scripts/jsd/main.js235ms225ms2ms3rd
https://www.googletagmanager.com/gtag/js?id=G-8MYC5SEFJ1&cx=c&gtm=4e6460215ms174ms37ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-KJ7QK4SN146ms116ms29ms3rd
https://openai.com/_next/static/chunks/07ab26e5-ebe71173fb97754b.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63110ms1ms109ms3rd
https://openai.com/_next/static/chunks/31854-2cd1e3cf4e8ba5d2.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f6392ms2ms90ms3rd

Showing top 10 of 12 scripts

F
JS Bundles
Action
61 scripts, 1.2 MB unused
FIX
61 scripts, 1.2 MB unused
Warning::
https://openai.com/_next/static/chunks/39334-0e775...: 155 KB unused (80%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://openai.com/_next/static/chunks/66332-2ab98...: 125 KB unused (60%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://openai.com/_next/static/chunks/32974-c132d...: 122 KB unused (87%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://openai.com/_next/static/chunks/46601-b68fa...: 114 KB unused (96%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://openai.com/_next/static/chunks/18d5b4bf-eb...: 72 KB unused (92%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.2 MB
1252 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://openai.com/_next/static/chunks/39334-0e7756423fce06ba.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63193 KB155 KB (80%)✓3rd
https://openai.com/_next/static/chunks/66332-2ab9821a742fb6dc.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63208 KB125 KB (60%)✓3rd
https://openai.com/_next/static/chunks/32974-c132db00f4b1c09a.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63141 KB122 KB (87%)✓3rd
https://openai.com/_next/static/chunks/46601-b68fa9ffc4104e5c.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63120 KB114 KB (96%)✓3rd
https://openai.com/_next/static/chunks/18d5b4bf-ebca743059771774.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f6379 KB72 KB (92%)✓3rd
https://openai.com/_next/static/chunks/28821-bbf7d15a0cb6953f.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63100 KB70 KB (73%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-8MYC5SEFJ1&cx=c&gtm=4e6460156 KB66 KB (42%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-KJ7QK4SN130 KB65 KB (50%)✓3rd
https://openai.com/_next/static/chunks/76296-f4d006a75df430f5.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f6393 KB64 KB (70%)✓3rd
https://openai.com/_next/static/chunks/79118-8f96f2898d1ae52f.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f6355 KB51 KB (94%)✓3rd

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

D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
max-age0Cache for 0 seconds
no-store—Never cache this response
no-cache—Cache but always revalidate first
must-revalidate—Must recheck with server after expiry
post-check0
pre-check0
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+
Image Optimization
11 images, 0 KB saveable
PASS
11 images, 0 KB saveable
Info::
All images are well-optimized
11 images 180 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+
Font Loading
3 fonts (148 KB)
PASS
3 fonts (148 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

148 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 16.0 s 18.0 s 20.0 s 22.0 s 24.0 s FCP 2.4 s LCP 23.1 shttps://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Medium.woff2OpenAISans-Medium.woff2 https://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Medium.woff2 — 50.1 KiB — 0 ms — font-display: swaphttps://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Semibold.woff2OpenAISans-Semibold.woff2 https://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Semibold.woff2 — 50.3 KiB — 0 ms — font-display: swaphttps://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Regular.woff2OpenAISans-Regular.woff2 https://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Regular.woff2 — 47.8 KiB — 0 ms — font-display: swap
OpenAISans-Medium.woff2 woff2 swap
Size 50 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
OpenAISans-Semibold.woff2 woff2 swap
Size 50 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
OpenAISans-Regular.woff2 woff2 swap
Size 48 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)
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
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
103 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
100% of JavaScript execution is third-party
First-party Third-party 5462ms · 1737KB · $73/mo
openai.com
Other
Costly
Execution 1072ms
Transfer 307 KB
Unused 13%
Monthly Cost $14/mo
openai.com
Other
Costly
Execution 988ms
Transfer 60 KB
Unused 36%
Monthly Cost $13/mo
Unattributable
Other
Costly
Execution 953ms
Transfer 0 KB
Monthly Cost $13/mo
openai.com
Other
Costly
Execution 772ms
Transfer 41 KB
Monthly Cost $10/mo
openai.com
Other
Costly
Execution 746ms
Transfer 10 KB
Monthly Cost $10/mo
openai.com
Other
Costly
Execution 235ms
Transfer 1 KB
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Costly
Execution 215ms
Transfer 156 KB
Unused 42%
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Optional
Execution 146ms
Transfer 130 KB
Unused 50%
Monthly Cost $2/mo
openai.com
Other
Optional
Execution 110ms
Transfer 338 KB
Monthly Cost $1/mo
openai.com
Other
Optional
Execution 92ms
Transfer 292 KB
Monthly Cost $1/mo
openai.com
Other
Optional
Execution 80ms
Transfer 208 KB
Unused 60%
Monthly Cost $1/mo
openai.com
Other
Optional
Execution 51ms
Transfer 193 KB
Unused 80%
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • openai.com adds 1072ms and costs ~$14/month
  • openai.com adds 988ms and costs ~$13/month
  • Unattributable adds 953ms and costs ~$13/month
  • openai.com adds 772ms and costs ~$10/month
  • openai.com adds 746ms and costs ~$10/month
  • openai.com adds 235ms and costs ~$3/month
  • Google Tag Manager adds 215ms and costs ~$3/month

100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

openai.com takes 1072ms 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

openai.com takes 988ms 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

Unattributable takes 953ms 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

openai.com takes 772ms 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

openai.com takes 746ms 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

openai.com takes 235ms 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

Google Tag Manager takes 215ms 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

50% of Google Tag Manager'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

60% of openai.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

80% of openai.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.

Send Feedback