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https://www.bing.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
89
GRADE
B
FIX
4
REVIEW
3
PASS
5
INFO
2

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

Mobile Desktop
79
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
69
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.

302 ms

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

1.09 s

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

179 ms

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

0.209

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

2.00 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.

3.75 s

Page Load Progression

556 ms
1.1 s
1.7 s
2.2 s
2.8 s
3.3 s
3.9 s
4.4 s
Checks
14
5 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
5.1 MB transferred, 343 requests
FIX
5.1 MB transferred, 343 requests
Critical::
Page weighs 13.8 MB (5.1 MB transferred)
Warning::
Images are 1.9 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.9 MB
Warning::
JavaScript is 1.6 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.6 MB
Warning::
343 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.1 g CO2 per page load
5.1 MB / 2.4 MB budget
5.1 MB transferred
343 requests
1.1 g CO2 per page load
Images 1.9 MiB 37%
JavaScript 1.6 MiB 32%
Other 1010.6 KiB 19%
Other 378.4 KiB 7%
CSS 132.6 KiB 3%
HTML 52.5 KiB 1%
Other 12.8 KiB 0%
Other 2.2 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

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

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
67% third-party, 0 ms blocking
FIX
67% third-party, 0 ms blocking
Warning::
Third-party code accounts for 67% of page weight (3.4 MiB of 5.1 MiB)
Info::
Third-party blocking time is low (0 ms)
33%
67%
First-party Third-party
D
JS Execution Cost
Action
2288ms total JS execution
FIX
2288ms total JS execution
Warning::
https://assets.msn.com/bundles/v1/bingHomepage/lat...: 650ms CPU time
Warning::
https://assets.msn.com/bundles/v1/bingHomepage/lat...: 359ms CPU time
Warning::
Unattributable: 347ms CPU time
Warning::
https://www.bing.com/: 325ms CPU time
Info::
https://r.bing.com/rp/w19dDk2py2mlGW2GYbXdcuuQfy0....: 240ms CPU time
Warning::
Third-party scripts: 1879ms (82% of total)

Main Thread Breakdown

Script Evaluation 57% Other 20% Style & Layout 8% Script Parsing & Compilation 6% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://assets.msn.com/bundles/v1/bingHomepage/latest/microsoft.edd09c236eeae714cc11.js650ms482ms16ms3rd
https://assets.msn.com/bundles/v1/bingHomepage/latest/common.d1757842ccb93b150d1c.js359ms260ms48ms3rd
Unattributable347ms34ms0ms3rd
https://www.bing.com/325ms23ms4ms1st
https://r.bing.com/rp/w19dDk2py2mlGW2GYbXdcuuQfy0.br.js240ms225ms9ms3rd
https://assets.msn.com/bundles/v1/bingHomepage/latest/social-bar-wc.60425ab86bbdc0589e07.js90ms65ms2ms3rd
https://www.bing.com/rp/U_ijXIZu_xhBRxPs1aGV2bq3vBo.br.js84ms53ms3ms1st
https://assets.msn.com/bundles/v1/bingHomepage/latest/experience.5ce3ca36e15fe40a5eb1.js72ms5ms22ms3rd
https://r.bing.com/rp/_IMVmfvcwkyuJTy52eloBVYz2W4.br.js67ms53ms2ms3rd
https://r.bing.com/rp/n23ANye7L3wtUcgKxoGHb7_ezc4.br.js55ms36ms0ms3rd
F
JS Bundles
Action
114 scripts, 829 KB unused
FIX
114 scripts, 829 KB unused
Warning::
https://assets.msn.com/bundles/v1/bingHomepage/lat...: 233 KB unused (45%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://r.bing.com/rp/w19dDk2py2mlGW2GYbXdcuuQfy0....: 81 KB unused (61%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://r.bing.com/rp/w19dDk2py2mlGW2GYbXdcuuQfy0....: 81 KB unused (61%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://assets.msn.com/bundles/v1/bingHomepage/lat...: 73 KB unused (38%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://r.bing.com/rp/5RUBu5dEYIDzWQtuZRVAHjBjuyc....: 62 KB unused (70%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 829 KB
829 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://assets.msn.com/bundles/v1/bingHomepage/latest/common.d1757842ccb93b150d1c.js514 KB233 KB (45%)✓3rd
https://r.bing.com/rp/w19dDk2py2mlGW2GYbXdcuuQfy0.br.js0 KB81 KB (61%)✓3rd
https://r.bing.com/rp/w19dDk2py2mlGW2GYbXdcuuQfy0.br.js133 KB81 KB (61%)✓3rd
https://assets.msn.com/bundles/v1/bingHomepage/latest/experience.5ce3ca36e15fe40a5eb1.js191 KB73 KB (38%)✓3rd
https://r.bing.com/rp/5RUBu5dEYIDzWQtuZRVAHjBjuyc.br.js90 KB62 KB (70%)✓3rd
https://r.bing.com/rp/5RUBu5dEYIDzWQtuZRVAHjBjuyc.br.js0 KB62 KB (70%)✓3rd
https://r.bing.com/rp/9uYIRoQB-ThMq970XKGeKvrMhL0.br.js64 KB46 KB (72%)✓3rd
https://r.bing.com/rp/9uYIRoQB-ThMq970XKGeKvrMhL0.br.js0 KB46 KB (72%)✓3rd
https://assets.msn.com/bundles/v1/bingHomepage/latest/experiences_bing-homepage-feed_dist_lazy-loadings_feedManager_js.5ccc66a960d3c893ce72.js62 KB34 KB (56%)✓3rd
https://assets.msn.com/bundles/v1/bingHomepage/latest/card-actions-wc.0f07467d206e8fb510d9.js45 KB31 KB (69%)✓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

B
Image Optimization
179 images, 0 KB saveable
REVIEW
179 images, 0 KB saveable
Info::
All images are well-optimized
179 images 1.9 MB
0 oversized -0 KB
167 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
private
REVIEW
private
Info::
Cache-Control header is set
Got: private
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
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
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
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
343 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
82% of JavaScript execution is third-party
First-party Third-party 1879ms · 875KB · $25/mo
assets.msn.com
Other
Costly
Execution 650ms
Transfer 115 KB
Unused 26%
Monthly Cost $9/mo
assets.msn.com
Other
Costly
Execution 359ms
Transfer 514 KB
Unused 45%
Monthly Cost $5/mo
Unattributable
Other
Costly
Execution 347ms
Transfer 0 KB
Monthly Cost $5/mo
r.bing.com
Other
Costly
Execution 240ms
Transfer 0 KB
Unused 61%
Monthly Cost $3/mo
assets.msn.com
Other
Optional
Execution 90ms
Transfer 30 KB
Monthly Cost $1/mo
assets.msn.com
Other
Optional
Execution 72ms
Transfer 191 KB
Unused 38%
Monthly Cost $1/mo
r.bing.com
Other
Optional
Execution 67ms
Transfer 24 KB
Monthly Cost $1/mo
r.bing.com
Other
Optional
Execution 55ms
Transfer 0 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • assets.msn.com adds 650ms and costs ~$9/month
  • assets.msn.com adds 359ms and costs ~$5/month
  • Unattributable adds 347ms and costs ~$5/month
  • r.bing.com adds 240ms and costs ~$3/month

82% 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

assets.msn.com takes 650ms 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

assets.msn.com takes 359ms 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 347ms 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

r.bing.com takes 240ms 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 r.bing.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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