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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
72
GRADE
C
FIX
5
REVIEW
1
PASS
8
INFO
2

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

Mobile Desktop
26
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
87
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.

3.68 s

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

28.87 s

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

7.75 s

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

0.115

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

9.13 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.

43.30 s

Page Load Progression

1.1 s
2.2 s
3.3 s
4.4 s
5.6 s
6.7 s
7.8 s
8.9 s
Checks
16
8 PASS 1 REVIEW 5 FIX
F
Page Weight Budget
Action
5.8 MB transferred, 251 requests
FIX
5.8 MB transferred, 251 requests
Critical::
Page weighs 20.5 MB (5.8 MB transferred)
Warning::
JavaScript is 5.2 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 5.2 MB
Info::
Fonts are 373 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 373 KB
Warning::
251 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.2 g CO2 per page load
5.8 MB / 2.4 MB budget
5.8 MB transferred
251 requests
1.2 g CO2 per page load
JavaScript 5.2 MiB 89%
Fonts 373.2 KiB 6%
CSS 165.1 KiB 3%
HTML 111.6 KiB 2%
Other 13.3 KiB 0%
Other 5.8 KiB 0%
Other 3.5 KiB 0%
Images 2.8 KiB 0%
Other 869 B 0%
Other 301 B 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

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
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (5.8 MiB of 5.8 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
17793ms total JS execution
FIX
17793ms total JS execution
Warning::
https://cdn.replit.com/_next/static/chunks/0i8wy8t...: 3470ms CPU time
Warning::
https://replit.com/: 3182ms CPU time
Warning::
https://cdn.replit.com/_next/static/chunks/01eyejq...: 2198ms CPU time
Warning::
https://cdn.replit.com/_next/static/chunks/0to4sxe...: 1757ms CPU time
Warning::
Unattributable: 1291ms CPU time
Warning::
Third-party scripts: 17793ms (100% of total)

Main Thread Breakdown

Script Evaluation 56% Style & Layout 14% Other 14% Script Parsing & Compilation 11%
ScriptTotalScriptingParse/CompileParty
https://cdn.replit.com/_next/static/chunks/0i8wy8tbht2ow.js3470ms2342ms16ms3rd
https://replit.com/3182ms21ms4ms3rd
https://cdn.replit.com/_next/static/chunks/01eyejqjhinfj.js2198ms1922ms21ms3rd
https://cdn.replit.com/_next/static/chunks/0to4sxecg1htq.js1757ms1536ms147ms3rd
Unattributable1291ms133ms0ms3rd
https://cdn.replit.com/_next/static/chunks/turbopack-0ysfnu9esvk6v.js962ms910ms2ms3rd
https://cdn.replit.com/_next/static/chunks/turbopack-0ejfz3q42gqc6.js684ms681ms2ms3rd
https://www.googletagmanager.com/gtag/js?id=G-MPJY3F1YEL&cx=c&_slc=1575ms482ms67ms3rd
https://js.stripe.com/acacia/stripe.js473ms339ms131ms3rd
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js376ms234ms119ms3rd

Showing top 10 of 28 scripts

F
JS Bundles
Action
182 scripts, 1.9 MB unused
FIX
182 scripts, 1.9 MB unused
Warning::
https://www.gstatic.com/recaptcha/releases/kUYUkUl...: 161 KB unused (45%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.gstatic.com/recaptcha/releases/kUYUkUl...: 161 KB unused (45%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.gstatic.com/recaptcha/releases/kUYUkUl...: 161 KB unused (45%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://js.stripe.com/acacia/stripe.js: 144 KB unused (64%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.replit.com/_next/static/chunks/0to4sxe...: 110 KB unused (90%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.9 MB
1930 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js363 KB161 KB (45%)✓3rd
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js0 KB161 KB (45%)✓3rd
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js363 KB161 KB (45%)✓3rd
https://js.stripe.com/acacia/stripe.js225 KB144 KB (64%)✓3rd
https://cdn.replit.com/_next/static/chunks/0to4sxecg1htq.js123 KB110 KB (90%)✓3rd
https://accounts.google.com/gsi/client93 KB69 KB (75%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-MPJY3F1YEL&cx=c&_slc=1172 KB68 KB (40%)✓3rd
https://www.google-analytics.com/gtm/js?id=OPT-TG46GJV&cid=1747007774.1775593704108 KB68 KB (62%)✓3rd
https://cdn.replit.com/_next/static/chunks/0lwq8bzhc8c1k.js91 KB67 KB (74%)✓3rd
https://cdn.replit.com/_next/static/chunks/0~l37myivhd-2.js75 KB66 KB (89%)✓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

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.

B
Image Optimization
8 images, 0 KB saveable
REVIEW
8 images, 0 KB saveable
Info::
All images are well-optimized
8 images 3 KB
0 oversized -0 KB
6 legacy format
0 missing dimensions CLS risk
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
8 fonts (373 KB)
PASS
8 fonts (373 KB)
Info::
8 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

8

373 KB total

Render-blocking

0

of 8

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 26.0 s 28.0 s 30.0 s FCP 3.7 s LCP 28.9 shttps://replit.com/public/fonts/ibm-plex-sans-v8-latin-regular.woff2ibm-plex-sans-v8-latin-... https://replit.com/public/fonts/ibm-plex-sans-v8-latin-regular.woff2 — 17.6 KiB — 0 ms — font-display: swaphttps://replit.com/public/fonts/ibm-plex-sans-v8-latin-italic.woff2ibm-plex-sans-v8-latin-... https://replit.com/public/fonts/ibm-plex-sans-v8-latin-italic.woff2 — 19.2 KiB — 0 ms — font-display: swaphttps://replit.com/public/fonts/ibm-plex-sans-v8-latin-500.woff2ibm-plex-sans-v8-latin-... https://replit.com/public/fonts/ibm-plex-sans-v8-latin-500.woff2 — 18.4 KiB — 0 ms — font-display: swaphttps://replit.com/public/fonts/ibm-plex-sans-v8-latin-500italic.woff2ibm-plex-sans-v8-latin-... https://replit.com/public/fonts/ibm-plex-sans-v8-latin-500italic.woff2 — 20.1 KiB — 0 ms — font-display: swaphttps://replit.com/public/fonts/ibm-plex-sans-v8-latin-600.woff2ibm-plex-sans-v8-latin-... https://replit.com/public/fonts/ibm-plex-sans-v8-latin-600.woff2 — 18.7 KiB — 0 ms — font-display: swaphttps://replit.com/public/fonts/ibm-plex-sans-v8-latin-600italic.woff2ibm-plex-sans-v8-latin-... https://replit.com/public/fonts/ibm-plex-sans-v8-latin-600italic.woff2 — 19.7 KiB — 0 ms — font-display: swaphttps://replit.com/public/fonts/ABCDiatypePlusVariable-Regular.woff2ABCDiatypePlusVariable-... https://replit.com/public/fonts/ABCDiatypePlusVariable-Regular.woff2 — 225.6 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 33.9 KiB — 0 ms — font-display: swap
ibm-plex-sans-v8-latin-... woff2 swap
Size 18 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm-plex-sans-v8-latin-... woff2 swap
Size 19 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm-plex-sans-v8-latin-... woff2 swap
Size 18 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm-plex-sans-v8-latin-... woff2 swap
Size 20 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm-plex-sans-v8-latin-... woff2 swap
Size 19 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm-plex-sans-v8-latin-... woff2 swap
Size 20 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ABCDiatypePlusVariable-... woff2 swap
Size 226 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
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 34 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 ~113 KB and ~226 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
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
251 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 17793ms · 1642KB · $236/mo
cdn.replit.com
Other
Costly
Execution 3470ms
Transfer 43 KB
Monthly Cost $46/mo
replit.com
Other
Costly
Execution 3182ms
Transfer 79 KB
Monthly Cost $42/mo
cdn.replit.com
Other
Costly
Execution 2198ms
Transfer 54 KB
Unused 52%
Monthly Cost $29/mo
cdn.replit.com
Other
Costly
Execution 1757ms
Transfer 123 KB
Unused 90%
Monthly Cost $23/mo
Unattributable
Other
Costly
Execution 1291ms
Transfer 0 KB
Monthly Cost $17/mo
cdn.replit.com
Other
Costly
Execution 962ms
Transfer 6 KB
Monthly Cost $13/mo
cdn.replit.com
Other
Costly
Execution 684ms
Transfer 6 KB
Monthly Cost $9/mo
Google Tag Manager
Tag Manager
Costly
Execution 575ms
Transfer 172 KB
Unused 40%
Monthly Cost $8/mo
Stripe
Payment
Essential
Execution 473ms
Transfer 225 KB
Unused 64%
Monthly Cost $6/mo
www.gstatic.com
Other
Costly
Execution 376ms
Transfer 0 KB
Unused 45%
Monthly Cost $5/mo
js.hcaptcha.com
Other
Costly
Execution 324ms
Transfer 86 KB
Unused 40%
Monthly Cost $4/mo
replit.com
Other
Costly
Execution 290ms
Transfer 90 KB
Unused 61%
Monthly Cost $4/mo
Segment
Analytics
Costly
Execution 276ms
Transfer 9 KB
Monthly Cost $4/mo
Google Analytics
Analytics
Costly
Execution 216ms
Transfer 108 KB
Unused 62%
Monthly Cost $3/mo
accounts.google.com
Other
Costly
Execution 205ms
Transfer 93 KB
Unused 75%
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Optional
Execution 181ms
Transfer 140 KB
Unused 37%
Monthly Cost $2/mo
replit.com
Other
Optional
Execution 172ms
Transfer 95 KB
Unused 36%
Monthly Cost $2/mo
cdn.replit.com
Other
Optional
Execution 171ms
Transfer 47 KB
Monthly Cost $2/mo
Facebook Pixel
Advertising
Optional
Execution 139ms
Transfer 36 KB
Monthly Cost $2/mo
cdn.replit.com
Other
Optional
Execution 131ms
Transfer 11 KB
Monthly Cost $2/mo
cdn.replit.com
Other
Optional
Execution 129ms
Transfer 20 KB
Monthly Cost $2/mo
Segment
Analytics
Optional
Execution 122ms
Transfer 22 KB
Monthly Cost $2/mo
apis.google.com
Other
Optional
Execution 99ms
Transfer 34 KB
Monthly Cost $1/mo
cdn.replit.com
Other
Optional
Execution 89ms
Transfer 28 KB
Monthly Cost $1/mo
cdn.replit.com
Other
Optional
Execution 79ms
Transfer 63 KB
Unused 99%
Monthly Cost $1/mo
Google Analytics
Analytics
Optional
Execution 78ms
Transfer 21 KB
Monthly Cost $1/mo
cdn.replit.com
Other
Optional
Execution 70ms
Transfer 0 KB
Monthly Cost $1/mo
sp.replit.com
Other
Optional
Execution 53ms
Transfer 30 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • cdn.replit.com adds 3470ms and costs ~$46/month
  • replit.com adds 3182ms and costs ~$42/month
  • cdn.replit.com adds 2198ms and costs ~$29/month
  • cdn.replit.com adds 1757ms and costs ~$23/month
  • Unattributable adds 1291ms and costs ~$17/month
  • cdn.replit.com adds 962ms and costs ~$13/month
  • cdn.replit.com adds 684ms and costs ~$9/month
  • Google Tag Manager adds 575ms and costs ~$8/month
  • www.gstatic.com adds 376ms and costs ~$5/month
  • js.hcaptcha.com adds 324ms and costs ~$4/month
  • replit.com adds 290ms and costs ~$4/month
  • Segment adds 276ms and costs ~$4/month
  • Google Analytics adds 216ms and costs ~$3/month
  • accounts.google.com adds 205ms 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

cdn.replit.com takes 3470ms 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

replit.com takes 3182ms 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.replit.com takes 2198ms 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

52% of cdn.replit.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.replit.com takes 1757ms 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

90% of cdn.replit.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 1291ms 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.replit.com takes 962ms 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.replit.com takes 684ms 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 575ms 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

64% of Stripe'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

www.gstatic.com takes 376ms 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

js.hcaptcha.com takes 324ms 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

replit.com takes 290ms 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

61% of replit.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

Segment takes 276ms 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 Analytics takes 216ms 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

62% of Google Analytics'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

accounts.google.com takes 205ms 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

75% of accounts.google.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

99% of cdn.replit.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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