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https://icloud.com

Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
69
GRADE
D
FIX
4
REVIEW
3
PASS
6
INFO
2

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

Mobile Desktop
80
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.
88
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.

538 ms

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

1.90 s

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

290 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.

880 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.90 s

Page Load Progression

385 ms
771 ms
1.2 s
1.5 s
1.9 s
2.3 s
2.7 s
3.1 s
Checks
15
6 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
3.4 MB transferred, 27 requests
FIX
3.4 MB transferred, 27 requests
Warning::
Page weighs 7.8 MB (3.4 MB transferred)
Warning::
JavaScript is 898 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 898 KB
Info::
27 HTTP requests
Info::
Estimated 0.72 g CO2 per page load
3.4 MB / 2.4 MB budget
3.4 MB transferred
27 requests
0.72 g CO2 per page load
Other 1.7 MiB 49%
JavaScript 897.9 KiB 26%
Other 477.2 KiB 14%
Images 319.6 KiB 9%
CSS 71.7 KiB 2%
HTML 10.5 KiB 0%
Other 2.8 KiB 0%
Other 828 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

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 (3.4 MiB of 3.4 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Bundles
Action
7 scripts, 577 KB unused
FIX
7 scripts, 577 KB unused
Warning::
https://www.icloud.com/system/icloud.com/2612Build...: 512 KB unused (67%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.icloud.com/system/icloud.com/2612Build...: 65 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.icloud.com/system/icloud.com/2612Build...: unminified — 28 KB could be saved
Warning::
https://www.icloud.com/system/icloud.com/2612Build...: unminified — 8 KB could be saved
Info::
Total unused JavaScript: 577 KB
577 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.js764 KB512 KB (67%)✓3rd
https://www.icloud.com/system/icloud.com/2612Build21/en-us/RootComponentRoute.js88 KB65 KB (74%)✗3rd
blob:https://www.icloud.com/92afd6c4-4927-4597-a2f7-7296fc573d550 KB—✓3rd
https://appleid.cdn-apple.com/appleauth/static/jsapi/authService.latest.min.js14 KB—✓3rd
https://www.icloud.com/system/icloud.com/2612Build21/en-us/vendors~RootComponentRoute.js32 KB—✗3rd
https://www.icloud.com/system/icloud.com/2612Build21/en-us/vendors~Routes-HomePageRoute.js347 KB—✓3rd
https://www.icloud.com/system/icloud.com/2612Build21/en-us/Routes-HomePageRoute.js128 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

F
Page Weight Inventory
Action
27 resources · 3.4 MB · 577 KB savings available
FIX
27 resources · 3.4 MB · 577 KB savings available
Warning::
Page weight 2.4 MB over 1MB target
Got: 3.4 MB Expected: ≤ 1 MB
Info::
~577 KB of savings available
Warning::
26 third-party resources (100% of weight)
Info::
5 resources over 200KB
27 resources · 3.4 MiB · 26 third-party 2.4 MiB over 1MB target
Media 49% · 1.7 MiB
JavaScript 39% · 1.3 MiB
Image 9% · 321.6 KiB
CSS 2% · 71.7 KiB
Document 0% · 10.5 KiB
Other 0% · 3.9 KiB

~577.0 KiB of savings available

Remove unused JavaScript: 577.0 KiB
B
Image Optimization
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Info::
All images are well-optimized
7 images 320 KB
0 oversized -0 KB
5 legacy format
0 missing dimensions CLS risk
B
JS Execution Cost
593ms total JS execution
REVIEW
593ms total JS execution
Warning::
https://www.icloud.com/system/icloud.com/2612Build...: 393ms CPU time
Info::
https://www.icloud.com/: 108ms CPU time
Info::
Unattributable: 92ms CPU time
Warning::
Third-party scripts: 593ms (100% of total)

Main Thread Breakdown

Script Evaluation 46% Script Parsing & Compilation 22% Other 19% Style & Layout 6% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.js393ms273ms114ms3rd
https://www.icloud.com/108ms13ms2ms3rd
Unattributable92ms7ms0ms3rd
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
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
A
HTTP Caching
max-age=3600 (1 hour)
PASS
max-age=3600 (1 hour)
Info::
Cache-Control header is set
Got: max-age=3600
Info::
Effective TTL: 1 hour (max-age=3600)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

max-age=3600

DirectiveValueMeaning
max-age3600Cache for 1 hour
Effective TTL: 3600 seconds
Network Waterfall
27 requests over 778ms
INFO
0 ms 500 ms 1.0 s 1.5 s FCP 538 ms LCP 1.9 shttps://icloud.com// https://icloud.com/ — 301 — 376 B — 12 ms — h2https://www.icloud.com/www.icloud.com/ https://www.icloud.com/ — 200 — 10.5 KiB — 21 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.jswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.js — 200 — 764.0 KiB — 55 ms — h2https://setup.icloud.com/setup/ws/1/validate?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=381e3246-0467-4391-a48b-0d40698be490&requestId=3653aad8-c175-4665-9f1d-8f563c9d26basetup.icloud.com/setup/ws/1/validat... https://setup.icloud.com/setup/ws/1/validate?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=381e3246-0467-4391-a48b-0d40698be490&requestId=3653aad8-c175-4665-9f1d-8f563c9d26ba — 421 — 1.4 KiB — 354 ms — http/1.1https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.csswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.css — 200 — 46.8 KiB — 15 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/images@1x.binwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/images@1x.bin — 200 — 828 B — 5 ms — h2blob:https://www.icloud.com/92afd6c4-4927-4597-a2f7-7296fc573d55www.icloud.com/92afd6c4-4927-4597-a... blob:https://www.icloud.com/92afd6c4-4927-4597-a2f7-7296fc573d55 — -1 — 0 B — 0 ms — https://www.icloud.com/locales/5/en-US.json?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=381e3246-0467-4391-a48b-0d40698be490www.icloud.com/locales/5/en-US.json... https://www.icloud.com/locales/5/en-US.json?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=381e3246-0467-4391-a48b-0d40698be490 — 200 — 1.4 KiB — 19 ms — h2data:image/webp;base64,UklGRiIAAABXRUJQVlA4IBYAAAAwAQCdASoBAAEADsD+JaQAA3AAAAAAdata:image/webp;base64,UklGRiIAAABX... data:image/webp;base64,UklGRiIAAABXRUJQVlA4IBYAAAAwAQCdASoBAAEADsD+JaQAA3AAAAAA — 200 — 0 B — 0 ms — datablob:https://www.icloud.com/6c17d7e9-4a43-446f-bb44-bd086ae923e5www.icloud.com/6c17d7e9-4a43-446f-b... blob:https://www.icloud.com/6c17d7e9-4a43-446f-bb44-bd086ae923e5 — 200 — 0 B — 1 ms — blobdata:text/css;base64,LmJyb3dzZXItbm90aWZpY2F0aW9ucy1zdWNjZXNzLWFsZXJ0IC50aXRsZTo6YmVmb3Jle2JhY2tncm…data:text/css;base64,LmJyb3dzZXItbm... data:text/css;base64,LmJyb3dzZXItbm90aWZpY2F0aW9ucy1zdWNjZXNzLWFsZXJ0IC50aXRsZTo6YmVmb3Jle2JhY2tncm… — 200 — 0 B — 0 ms — datahttps://appleid.cdn-apple.com/appleauth/static/jsapi/authService.latest.min.jsappleid.cdn-apple.com/appleauth/sta... https://appleid.cdn-apple.com/appleauth/static/jsapi/authService.latest.min.js — 200 — 14.4 KiB — 18 ms — http/1.1https://www.icloud.com/system/icloud.com/2612Build21/0e4e931e06552e87f2fdff2832e11bb9.pngwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/0e4e931e06552e87f2fdff2832e11bb9.png — 200 — 45.6 KiB — 15 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/06b68855764eb0e23f269ed4ef7935f0.pngwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/06b68855764eb0e23f269ed4ef7935f0.png — 200 — 66.8 KiB — 15 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/7cb9ecdad2b384754de394732519f658.pngwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/7cb9ecdad2b384754de394732519f658.png — 200 — 203.5 KiB — 23 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/fpo@1x.mp4www.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/fpo@1x.mp4 — 206 — 224.5 KiB — 32 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/fpo@1x.mp4www.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/fpo@1x.mp4 — 206 — 20.2 KiB — 20 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/6.main.csswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/6.main.css — 200 — 1.2 KiB — 7 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/vendors~RootComponentRoute.jswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/vendors~RootComponentRoute.js — 200 — 31.9 KiB — 21 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/2.main.csswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/2.main.css — 200 — 23.7 KiB — 11 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/RootComponentRoute.jswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/RootComponentRoute.js — 200 — 87.6 KiB — 25 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/wallpaper.svgwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/wallpaper.svg — 200 — 1.8 KiB — 17 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/wallpaper_dark.svgwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/wallpaper_dark.svg — 200 — 1.9 KiB — 18 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/fpo@1x.mp4www.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/fpo@1x.mp4 — 206 — 1.4 MiB — 87 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/favicons/default-favicon-light-32x32.pngwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/favicons/default-favicon-light-32x32.png — 200 — 2.0 KiB — 22 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/vendors~Routes-HomePageRoute.jswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/vendors~Routes-HomePageRoute.js — 200 — 346.6 KiB — 44 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/Routes-HomePageRoute.jswww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/Routes-HomePageRoute.js — 200 — 128.1 KiB — 41 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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 593ms · 775KB · $8/mo
www.icloud.com
Other
Costly
Execution 393ms
Transfer 764 KB
Unused 67%
Monthly Cost $5/mo
www.icloud.com
Other
Optional
Execution 108ms
Transfer 11 KB
Monthly Cost $1/mo
Unattributable
Other
Optional
Execution 92ms
Transfer 0 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • www.icloud.com adds 393ms and costs ~$5/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

www.icloud.com takes 393ms 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

67% of www.icloud.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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