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https://www.yelp.com

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
78
GRADE
C
FIX
3
REVIEW
4
PASS
7
INFO
2

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

Mobile Desktop
43
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
92
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.

5.41 s

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

8.56 s

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

744 ms

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

0.013

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

5.41 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.

14.82 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
7 PASS 4 REVIEW 3 FIX
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 (1.8 MiB of 1.8 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
4235ms total JS execution
FIX
4235ms total JS execution
Warning::
Unattributable: 1921ms CPU time
Warning::
https://s3-media0.fl.yelpcdn.com/assets/public/mod...: 1385ms CPU time
Warning::
https://www.yelp.fr/: 614ms CPU time
Warning::
https://js.datadome.co/tags.js: 258ms CPU time
Info::
https://s3-media0.fl.yelpcdn.com/assets/srv0/cdn_a...: 56ms CPU time
Warning::
Third-party scripts: 4235ms (100% of total)

Main Thread Breakdown

Script Evaluation 50% Other 33% Style & Layout 8% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
Unattributable1921ms718ms0ms3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_shared-04db01acf929d247523f4c52ac2c8215935f52b9.yji-30d1c513c6e158ab.mjs1385ms1168ms4ms3rd
https://www.yelp.fr/614ms19ms23ms3rd
https://js.datadome.co/tags.js258ms234ms12ms3rd
https://s3-media0.fl.yelpcdn.com/assets/srv0/cdn_assets/35b9d8c2cb77/assets/vendor/es-module-shims/1.10.0/es-module-shims.min.js56ms48ms5ms3rd
F
JS Bundles
Action
55 scripts, 444 KB unused
FIX
55 scripts, 444 KB unused
Warning::
https://s3-media0.fl.yelpcdn.com/assets/public/mod...: 169 KB unused (56%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://s3-media0.fl.yelpcdn.com/assets/public/mod...: 168 KB unused (70%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://s3-media0.fl.yelpcdn.com/assets/public/mod...: 65 KB unused (87%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://s3-media0.fl.yelpcdn.com/assets/srv0/cdn_a...: 22 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://s3-media0.fl.yelpcdn.com/assets/srv0/cdn_a...: unminified — 10 KB could be saved
Warning::
https://s3-media0.fl.yelpcdn.com/assets/public/mod...: 20 KB unused (88%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 444 KB
444 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_shared-04db01acf929d247523f4c52ac2c8215935f52b9.yji-30d1c513c6e158ab.mjs304 KB169 KB (56%)✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_shared-137874594457bb19444d508ffc1b8360f6254e3a.yji-62489aa171f876f5.mjs244 KB168 KB (70%)✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_lib-lottie-web-5.13.0.yji-ff94554bd2c9ef61.mjs75 KB65 KB (87%)✓3rd
https://s3-media0.fl.yelpcdn.com/assets/srv0/cdn_assets/d92e3267df3b/assets/vendor/react-dom-client/19.2.4/esm/react-dom-client.production.mjs60 KB22 KB (36%)✗3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_shared-b2f0353fe714602062eef7e1466f94411bd11e09.yji-6cb2cb9fddec323c.mjs23 KB20 KB (88%)✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_lib-yelp-react-component-app-pitch-8.24.0.yji-f2fd41a67c2d7b9e.mjs4 KB—✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_shared-d8e874d08c5f244f924bbeeea5ea41e9c1098ca9.yji-f554a241a339deaa.mjs7 KB—✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_runtime~gondola-mobile-homepage.yji-fc3fe78d8dbd4c6f.mjs2 KB—✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_lib-yelp-react-component-badge-20.0.9.yji-23107618d3a8d662.mjs2 KB—✓3rd
https://s3-media0.fl.yelpcdn.com/assets/public/module_yelp-frontend_lib-yelp-react-component-photo-box-21.0.14.yji-bc2a1caf2dcfb3fd.mjs3 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

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
Page Weight Budget
Action
1.8 MB transferred, 93 requests
REVIEW
1.8 MB transferred, 93 requests
Info::
Page weighs 4.9 MB (1.8 MB transferred)
Warning::
JavaScript is 1.1 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.1 MB
Info::
93 HTTP requests
Info::
Estimated 0.37 g CO2 per page load
1.8 MB / 2.4 MB budget
1.8 MB transferred
93 requests
0.37 g CO2 per page load
JavaScript 1.1 MiB 60%
Images 390.8 KiB 22%
Fonts 149.7 KiB 8%
Other 103.0 KiB 6%
HTML 60.4 KiB 3%
CSS 27.0 KiB 1%
Other 1.3 KiB 0%
Other 432 B 0%
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

B
Image Optimization
21 images, 0 KB saveable
REVIEW
21 images, 0 KB saveable
Info::
All images are well-optimized
21 images 391 KB
0 oversized -0 KB
21 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
no-cache
REVIEW
no-cache
Info::
Cache-Control header is set
Got: no-cache
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-cache

DirectiveValueMeaning
no-cache—Cache but always revalidate first
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
5 fonts (150 KB)
PASS
5 fonts (150 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

150 KB total

Render-blocking

0

of 5

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 6.0 s 7.0 s 8.0 s FCP 5.4 s LCP 8.6 shttps://s3-media0.fl.yelpcdn.com/assets/public/open-sans-regular.yji-0ffa35321c9a4edc.woff2open-sans-regular.yji-0... https://s3-media0.fl.yelpcdn.com/assets/public/open-sans-regular.yji-0ffa35321c9a4edc.woff2 — 43.4 KiB — 0 ms — font-display: swaphttps://s3-media0.fl.yelpcdn.com/assets/public/open-sans-semibold.yji-7a0d1b8cfe27b45a.woff2open-sans-semibold.yji-... https://s3-media0.fl.yelpcdn.com/assets/public/open-sans-semibold.yji-7a0d1b8cfe27b45a.woff2 — 45.4 KiB — 0 ms — font-display: swaphttps://s3-media0.fl.yelpcdn.com/assets/public/open-sans-bold.yji-5d14ee0b48af7d8b.woff2open-sans-bold.yji-5d14... https://s3-media0.fl.yelpcdn.com/assets/public/open-sans-bold.yji-5d14ee0b48af7d8b.woff2 — 45.3 KiB — 0 ms — font-display: swaphttps://s3-media0.fl.yelpcdn.com/assets/public/poppins-bold.yji-0319f02e4fd3c5a4.woff2poppins-bold.yji-0319f0... https://s3-media0.fl.yelpcdn.com/assets/public/poppins-bold.yji-0319f02e4fd3c5a4.woff2 — 7.8 KiB — 0 ms — font-display: swaphttps://s3-media0.fl.yelpcdn.com/assets/public/poppins-medium.yji-6a722094612266f8.woff2poppins-medium.yji-6a72... https://s3-media0.fl.yelpcdn.com/assets/public/poppins-medium.yji-6a722094612266f8.woff2 — 7.8 KiB — 0 ms — font-display: swap
open-sans-regular.yji-0... woff2 swap
Size 43 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
open-sans-semibold.yji-... woff2 swap
Size 45 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
open-sans-bold.yji-5d14... woff2 swap
Size 45 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
poppins-bold.yji-0319f0... woff2 swap
Size 8 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
poppins-medium.yji-6a72... woff2 swap
Size 8 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
15 hints, 0 missing preconnects
PASS
15 hints, 0 missing preconnects
Info::
Page uses 15 resource hint(s)

Current Resource Hints

preconnect
—
preload
+5
15
dns-prefetch
—
prefetch
—

15 resource hints configured

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
Network Waterfall
93 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 4235ms · 419KB · $56/mo
Unattributable
Other
Costly
Execution 1921ms
Transfer 0 KB
Monthly Cost $26/mo
s3-media0.fl.yelpcdn.com
Other
Costly
Execution 1385ms
Transfer 304 KB
Unused 56%
Monthly Cost $18/mo
www.yelp.fr
Other
Costly
Execution 614ms
Transfer 60 KB
Monthly Cost $8/mo
js.datadome.co
Other
Costly
Execution 258ms
Transfer 43 KB
Monthly Cost $3/mo
s3-media0.fl.yelpcdn.com
Other
Optional
Execution 56ms
Transfer 12 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 1921ms and costs ~$26/month
  • s3-media0.fl.yelpcdn.com adds 1385ms and costs ~$18/month
  • www.yelp.fr adds 614ms and costs ~$8/month
  • js.datadome.co adds 258ms 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

Unattributable takes 1921ms 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

s3-media0.fl.yelpcdn.com takes 1385ms 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 s3-media0.fl.yelpcdn.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

www.yelp.fr takes 614ms 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.datadome.co takes 258ms 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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