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https://stripe.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
80
GRADE
B
FIX
3
REVIEW
4
PASS
5
INFO
2

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

Mobile Desktop
56
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.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

1.14 s

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

1.20 s

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

18.40 s

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

0.015

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

3.78 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.

34.30 s

Page Load Progression

2.2 s
4.4 s
6.5 s
8.7 s
10.9 s
13.1 s
15.3 s
17.5 s
Checks
14
5 PASS 4 REVIEW 3 FIX
D
Third-Party Impact
Action
90% third-party, 0 ms blocking
FIX
90% third-party, 0 ms blocking
Warning::
Third-party code accounts for 90% of page weight (1.6 MiB of 1.8 MiB)
Info::
Third-party blocking time is low (0 ms)
90%
First-party Third-party
F
JS Execution Cost
Action
34591ms total JS execution
FIX
34591ms total JS execution
Warning::
https://b.stripecdn.com/mkt-ssr-statics/assets/_ne...: 32986ms CPU time
Warning::
https://b.stripecdn.com/mkt-ssr-statics/assets/_ne...: 537ms CPU time
Warning::
https://stripe.com/en-fr: 322ms CPU time
Warning::
Unattributable: 322ms CPU time
Info::
https://b.stripecdn.com/mkt-ssr-statics/assets/_ne...: 175ms CPU time
Warning::
Third-party scripts: 34269ms (99% of total)

Main Thread Breakdown

Other 94% Script Evaluation 3%
ScriptTotalScriptingParse/CompileParty
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/50582.fb4a3d13071d1490.js32986ms464ms2ms3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/framework-9f89521118404fe7.js537ms359ms8ms3rd
https://stripe.com/en-fr322ms2ms0ms1st
Unattributable322ms37ms0ms3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/pages/_app-c498e8e0ffe11922.js175ms113ms49ms3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/84246.854c27f9d542172f.js91ms46ms2ms3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/pages/index-bc82c870ad827b6d.js90ms63ms22ms3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/48015-dee80f6e96192d69.js69ms4ms0ms3rd
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

C
Page Weight Budget
Action
1.8 MB transferred, 111 requests
REVIEW
1.8 MB transferred, 111 requests
Info::
Page weighs 6.8 MB (1.8 MB transferred)
Warning::
JavaScript is 1.3 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.3 MB
Warning::
111 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.38 g CO2 per page load
1.8 MB / 2.4 MB budget
1.8 MB transferred
111 requests
0.38 g CO2 per page load
JavaScript 1.3 MiB 74%
HTML 169.0 KiB 9%
Images 143.6 KiB 8%
Fonts 70.1 KiB 4%
CSS 60.8 KiB 3%
Other 20.7 KiB 1%
Other 10.3 KiB 1%
0 2.4 MB 4.9 MB
Approaching limit

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

B
Image Optimization
9 images, 0 KB saveable
REVIEW
9 images, 0 KB saveable
Info::
All images are well-optimized
9 images 144 KB
0 oversized -0 KB
4 legacy format
0 missing dimensions CLS risk
C
JS Bundles
Action
79 scripts, 226 KB unused
REVIEW
79 scripts, 226 KB unused
Warning::
https://b.stripecdn.com/mkt-ssr-statics/assets/_ne...: 105 KB unused (47%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://b.stripecdn.com/mkt-ssr-statics/assets/_ne...: 79 KB unused (20%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://b.stripecdn.com/mkt-ssr-statics/assets/_ne...: 42 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 226 KB
226 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/pages/index-bc82c870ad827b6d.js221 KB105 KB (47%)✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/pages/_app-c498e8e0ffe11922.js397 KB79 KB (20%)✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/c67c952e-7f65a464f661b1d2.js57 KB42 KB (74%)✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/2791.83aa5fb914de3e9d.js1 KB—✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/15263.83460f5b8af8173e.js1 KB—✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/35729.33c2cdc4d27e8533.js2 KB—✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/34552.fae148eb6b06113b.js2 KB—✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/25879.d69b55cd25254173.js2 KB—✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/76629.396a50238922b152.js2 KB—✓3rd
https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/chunks/52643.2d78e2446d39abbd.js3 KB—✓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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

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
2 fonts (70 KB)
PASS
2 fonts (70 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

70 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 1.1 s LCP 1.2 shttps://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/media/Sohne.cb178166.woff2Sohne.cb178166.woff2 https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/media/Sohne.cb178166.woff2 — 58.0 KiB — 0 ms — font-display: swaphttps://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/media/SourceCodePro-Medium.f5ba3e6a.woff2SourceCodePro-Medium.f5... https://b.stripecdn.com/mkt-ssr-statics/assets/_next/static/media/SourceCodePro-Medium.f5ba3e6a.woff2 — 12.1 KiB — 0 ms — font-display: swap
Sohne.cb178166.woff2 woff2 swap
Size 58 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
SourceCodePro-Medium.f5... woff2 swap
Size 12 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
Network Waterfall
111 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
99% of JavaScript execution is third-party
First-party Third-party 34269ms · 716KB · €144/mo
b.stripecdn.com
Other
Costly
Execution 32986ms
Transfer 23 KB
Monthly Cost €138/mo
b.stripecdn.com
Other
Costly
Execution 537ms
Transfer 43 KB
Monthly Cost €2/mo
Unattributable
Other
Costly
Execution 322ms
Transfer 0 KB
Monthly Cost €1/mo
b.stripecdn.com
Other
Optional
Execution 175ms
Transfer 397 KB
Unused 20%
Monthly Cost €1/mo
b.stripecdn.com
Other
Optional
Execution 91ms
Transfer 27 KB
Monthly Cost €0/mo
b.stripecdn.com
Other
Optional
Execution 90ms
Transfer 221 KB
Unused 47%
Monthly Cost €0/mo
b.stripecdn.com
Other
Optional
Execution 69ms
Transfer 6 KB
Monthly Cost €0/mo

These scripts may cost more than they're worth

  • b.stripecdn.com adds 32986ms and costs ~€138/month
  • b.stripecdn.com adds 537ms and costs ~€2/month
  • Unattributable adds 322ms and costs ~€1/month

99% 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

b.stripecdn.com takes 32986ms 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

b.stripecdn.com takes 537ms 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 322ms 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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