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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
74
GRADE
C
FIX
4
REVIEW
1
PASS
7
INFO
2

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

Mobile Desktop
65
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
97
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.

690 ms

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

5.30 s

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

200 ms

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.

2.45 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.

5.35 s

Page Load Progression

606 ms
1.2 s
1.8 s
2.4 s
3.0 s
3.6 s
4.2 s
4.9 s
Checks
14
7 PASS 1 REVIEW 4 FIX
F
Page Weight Budget
Action
5.0 MB transferred, 112 requests
FIX
5.0 MB transferred, 112 requests
Critical::
Page weighs 16.3 MB (5.0 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::
Images are 1.2 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.2 MB
Warning::
112 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.0 g CO2 per page load
5.0 MB / 2.4 MB budget
5.0 MB transferred
112 requests
1.0 g CO2 per page load
JavaScript 3.2 MiB 64%
Images 1.2 MiB 25%
Other 333.0 KiB 7%
Fonts 148.2 KiB 3%
CSS 67.2 KiB 1%
HTML 41.4 KiB 1%
Other 2.9 KiB 0%
Other 1.3 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

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

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 (5.0 MiB of 5.0 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
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...: 113 KB unused (95%)
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
1251 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 KB113 KB (95%)✓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_FfVqnoChcS7FLNSpbGCvwgNA3f63101 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
C
JS Execution Cost
Action
1152ms total JS execution
REVIEW
1152ms total JS execution
Warning::
https://openai.com/_next/static/chunks/32974-c132d...: 425ms CPU time
Info::
Unattributable: 235ms CPU time
Info::
https://openai.com/_next/static/chunks/72002-2f6e1...: 202ms CPU time
Info::
https://openai.com/: 170ms CPU time
Info::
https://openai.com/_next/static/chunks/main-app-67...: 63ms CPU time
Warning::
Third-party scripts: 1152ms (100% of total)

Main Thread Breakdown

Script Evaluation 57% Script Parsing & Compilation 17% Other 15% Style & Layout 7%
ScriptTotalScriptingParse/CompileParty
https://openai.com/_next/static/chunks/32974-c132db00f4b1c09a.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63425ms412ms9ms3rd
Unattributable235ms51ms0ms3rd
https://openai.com/_next/static/chunks/72002-2f6e1dde422f088e.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f63202ms165ms10ms3rd
https://openai.com/170ms17ms13ms3rd
https://openai.com/_next/static/chunks/main-app-67d4f3cb160e820c.js?dpl=dpl_FfVqnoChcS7FLNSpbGCvwgNA3f6363ms63ms0ms3rd
https://openai.com/cdn-cgi/challenge-platform/scripts/jsd/main.js57ms54ms1ms3rd
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
17 images, 0 KB saveable
PASS
17 images, 0 KB saveable
Info::
All images are well-optimized
17 images 1.2 MB
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 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s FCP 690 ms LCP 5.3 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-Regular.woff2OpenAISans-Regular.woff2 https://cdn.openai.com/common/fonts/openai-sans/v2/OpenAISans-Regular.woff2 — 47.8 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 — 50.2 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-Regular.woff2 woff2 swap
Size 48 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
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+
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
112 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 1152ms · 243KB · $15/mo
openai.com
Other
Costly
Execution 425ms
Transfer 141 KB
Unused 87%
Monthly Cost $6/mo
Unattributable
Other
Costly
Execution 235ms
Transfer 0 KB
Monthly Cost $3/mo
openai.com
Other
Costly
Execution 202ms
Transfer 59 KB
Unused 36%
Monthly Cost $3/mo
openai.com
Other
Optional
Execution 170ms
Transfer 41 KB
Monthly Cost $2/mo
openai.com
Other
Optional
Execution 63ms
Transfer 1 KB
Monthly Cost $1/mo
openai.com
Other
Optional
Execution 57ms
Transfer 1 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • openai.com adds 425ms and costs ~$6/month
  • Unattributable adds 235ms and costs ~$3/month
  • openai.com adds 202ms 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 425ms 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

87% 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

Unattributable 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

openai.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

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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