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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
69
GRADE
D
FIX
5
REVIEW
2
PASS
8
INFO
2

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

Mobile Desktop
48
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.

2.05 s

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

12.72 s

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

1.40 s

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

0.007

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

2.40 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.

13.26 s

Page Load Progression

386 ms
772 ms
1.2 s
1.5 s
1.9 s
2.3 s
2.7 s
3.1 s
Checks
17
8 PASS 2 REVIEW 5 FIX
F
Page Weight Budget
Action
4.0 MB transferred, 32 requests
FIX
4.0 MB transferred, 32 requests
Critical::
Page weighs 8.6 MB (4.0 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::
Fonts are 688 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 688 KB
Info::
32 HTTP requests
Info::
Estimated 0.83 g CO2 per page load
4.0 MB / 2.4 MB budget
4.0 MB transferred
32 requests
0.83 g CO2 per page load
Other 1.5 MiB 38%
JavaScript 897.9 KiB 22%
Fonts 688.2 KiB 17%
Other 477.2 KiB 12%
Images 377.6 KiB 9%
CSS 73.3 KiB 2%
HTML 10.5 KiB 0%
Other 2.8 KiB 0%
Other 827 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

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 (4.0 MiB of 4.0 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
D
JS Execution Cost
Action
2441ms total JS execution
FIX
2441ms total JS execution
Warning::
https://www.icloud.com/system/icloud.com/2612Build...: 1596ms CPU time
Warning::
Unattributable: 362ms CPU time
Warning::
https://www.icloud.com/: 270ms CPU time
Info::
https://www.icloud.com/system/icloud.com/2612Build...: 116ms CPU time
Info::
https://www.icloud.com/system/icloud.com/2612Build...: 96ms CPU time
Warning::
Third-party scripts: 2441ms (100% of total)

Main Thread Breakdown

Script Evaluation 48% Script Parsing & Compilation 23% Other 17% Style & Layout 7% Parse HTML & CSS 5%
ScriptTotalScriptingParse/CompileParty
https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.js1596ms1100ms457ms3rd
Unattributable362ms15ms0ms3rd
https://www.icloud.com/270ms49ms8ms3rd
https://www.icloud.com/system/icloud.com/2612Build21/en-us/RootComponentRoute.js116ms35ms78ms3rd
https://www.icloud.com/system/icloud.com/2612Build21/en-us/main.css96ms0ms0ms3rd
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/c65d2eff-fa3f-428c-b0e2-6e812d5b30760 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
32 resources · 4.0 MB · 577 KB savings available
FIX
32 resources · 4.0 MB · 577 KB savings available
Warning::
Page weight 3.0 MB over 1MB target
Got: 4.0 MB Expected: ≤ 1 MB
Info::
~577 KB of savings available
Warning::
31 third-party resources (100% of weight)
Info::
6 resources over 200KB
32 resources · 4.0 MiB · 31 third-party 3.0 MiB over 1MB target
Media 38% · 1.5 MiB
JavaScript 34% · 1.3 MiB
Font 17% · 688.2 KiB
Image 9% · 379.7 KiB
CSS 2% · 73.3 KiB
Document 0% · 10.5 KiB
Other 0% · 3.9 KiB

~576.9 KiB of savings available

Remove unused JavaScript: 576.9 KiB
B
Image Optimization
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Info::
All images are well-optimized
7 images 378 KB
0 oversized -0 KB
5 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

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
4 fonts (688 KB)
PASS
4 fonts (688 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

688 KB total

Render-blocking

0

of 4

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 FCP 2.0 s LCP 12.7 shttps://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_regular.woff2sf-pro-display_regular.... https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_regular.woff2 — 115.1 KiB — 50 ms — font-display: swaphttps://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_regular.woff2sf-pro-text_regular.woff2 https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_regular.woff2 — 216.2 KiB — 60 ms — font-display: swaphttps://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_semibold.woff2sf-pro-display_semibold... https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_semibold.woff2 — 127.2 KiB — 80 ms — font-display: swaphttps://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_semibold.woff2sf-pro-text_semibold.woff2 https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_semibold.woff2 — 229.6 KiB — 74 ms — font-display: swap
sf-pro-display_regular.... woff2 swap
Size 115 KB
Load time 50 ms
Start 47 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
sf-pro-text_regular.woff2 woff2 swap
Size 216 KB
Load time 60 ms
Start 47 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
sf-pro-display_semibold... woff2 swap
Size 127 KB
Load time 80 ms
Start 47 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
sf-pro-text_semibold.woff2 woff2 swap
Size 230 KB
Load time 74 ms
Start 48 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
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 ~344 KB and ~688 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
13 hints, 0 missing preconnects
PASS
13 hints, 0 missing preconnects
Info::
Page uses 13 resource hint(s)

Current Resource Hints

preconnect
3
preload
7
dns-prefetch
3
prefetch
—

13 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
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
32 requests over 782ms
INFO
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s FCP 2.0 s LCP 12.7 shttps://icloud.com// https://icloud.com/ — 301 — 376 B — 11 ms — h2https://www.icloud.com/www.icloud.com/ https://www.icloud.com/ — 200 — 10.5 KiB — 16 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 — 91 ms — h2https://www.apple.com/wss/fonts/?families=SF+Pro,v3www.apple.com/wss/fonts/?families=S... https://www.apple.com/wss/fonts/?families=SF+Pro,v3 — 200 — 1.7 KiB — 44 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_regular.woff2www.apple.com/wss/fonts/SF-Pro-Disp... https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_regular.woff2 — 200 — 115.1 KiB — 50 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_regular.woff2www.apple.com/wss/fonts/SF-Pro-Text... https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_regular.woff2 — 200 — 216.2 KiB — 60 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_semibold.woff2www.apple.com/wss/fonts/SF-Pro-Disp... https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_semibold.woff2 — 200 — 127.2 KiB — 80 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_semibold.woff2www.apple.com/wss/fonts/SF-Pro-Text... https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_semibold.woff2 — 200 — 229.6 KiB — 74 ms — h2https://setup.icloud.com/setup/ws/1/validate?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=62bb9e55-38ca-466d-b25c-3364add10561&requestId=73b57116-147d-4201-8951-8b774b8367dfsetup.icloud.com/setup/ws/1/validat... https://setup.icloud.com/setup/ws/1/validate?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=62bb9e55-38ca-466d-b25c-3364add10561&requestId=73b57116-147d-4201-8951-8b774b8367df — 421 — 1.4 KiB — 142 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 — 48 ms — h2https://www.icloud.com/system/icloud.com/2612Build21/en-us/images@2x.binwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/en-us/images@2x.bin — 200 — 827 B — 5 ms — h2blob:https://www.icloud.com/c65d2eff-fa3f-428c-b0e2-6e812d5b3076www.icloud.com/c65d2eff-fa3f-428c-b... blob:https://www.icloud.com/c65d2eff-fa3f-428c-b0e2-6e812d5b3076 — -1 — 0 B — 0 ms — https://www.icloud.com/locales/5/en-US.json?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=62bb9e55-38ca-466d-b25c-3364add10561www.icloud.com/locales/5/en-US.json... https://www.icloud.com/locales/5/en-US.json?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=62bb9e55-38ca-466d-b25c-3364add10561 — 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 — 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 — 14 ms — http/1.1blob:https://www.icloud.com/645dd6b5-0e3d-4be0-a385-81cf68e81ffdwww.icloud.com/645dd6b5-0e3d-4be0-a... blob:https://www.icloud.com/645dd6b5-0e3d-4be0-a385-81cf68e81ffd — 200 — 0 B — 1 ms — blobhttps://www.icloud.com/system/icloud.com/2612Build21/564be320e7a67acee204043935e41647.pngwww.icloud.com/system/icloud.com/26... https://www.icloud.com/system/icloud.com/2612Build21/564be320e7a67acee204043935e41647.png — 200 — 103.7 KiB — 8 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 — 13 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 — 20 ms — h2data:text/css;base64,LmJyb3dzZXItbm90aWZpY2F0aW9ucy1zdWNjZXNzLWFsZXJ0IC50aXRsZTo6YmVmb3Jle2JhY2tncm…data:text/css;base64,LmJyb3dzZXItbm... data:text/css;base64,LmJyb3dzZXItbm90aWZpY2F0aW9ucy1zdWNjZXNzLWFsZXJ0IC50aXRsZTo6YmVmb3Jle2JhY2tncm… — 200 — 0 B — 0 ms — datahttps://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 — 128.4 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 — 20.2 KiB — 19 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 — 15 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 — 28 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 — 21 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 — 25 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 — 12 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 — 1.3 MiB — 90 ms — h2
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s FCP 2.0 s LCP 12.7 shttps://icloud.com// https://icloud.com/ — 301 — 376 B — 11 ms — h2https://www.icloud.com/www.icloud.com/ https://www.icloud.com/ — 200 — 10.5 KiB — 16 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 — 91 ms — h2https://www.apple.com/wss/fonts/?families=SF+Pro,v3www.apple.com/wss/fonts/?families=S... https://www.apple.com/wss/fonts/?families=SF+Pro,v3 — 200 — 1.7 KiB — 44 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_regular.woff2www.apple.com/wss/fonts/SF-Pro-Disp... https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_regular.woff2 — 200 — 115.1 KiB — 50 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_regular.woff2www.apple.com/wss/fonts/SF-Pro-Text... https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_regular.woff2 — 200 — 216.2 KiB — 60 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_semibold.woff2www.apple.com/wss/fonts/SF-Pro-Disp... https://www.apple.com/wss/fonts/SF-Pro-Display/v3/sf-pro-display_semibold.woff2 — 200 — 127.2 KiB — 80 ms — h2https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_semibold.woff2www.apple.com/wss/fonts/SF-Pro-Text... https://www.apple.com/wss/fonts/SF-Pro-Text/v3/sf-pro-text_semibold.woff2 — 200 — 229.6 KiB — 74 ms — h2https://setup.icloud.com/setup/ws/1/validate?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=62bb9e55-38ca-466d-b25c-3364add10561&requestId=73b57116-147d-4201-8951-8b774b8367dfsetup.icloud.com/setup/ws/1/validat... https://setup.icloud.com/setup/ws/1/validate?clientBuildNumber=2612Build21&clientMasteringNumber=2612Build21&clientId=62bb9e55-38ca-466d-b25c-3364add10561&requestId=73b57116-147d-4201-8951-8b774b8367df — 421 — 1.4 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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 — 42 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 2441ms · 909KB · $32/mo
www.icloud.com
Other
Costly
Execution 1596ms
Transfer 764 KB
Unused 67%
Monthly Cost $21/mo
Unattributable
Other
Costly
Execution 362ms
Transfer 0 KB
Monthly Cost $5/mo
www.icloud.com
Other
Costly
Execution 270ms
Transfer 11 KB
Monthly Cost $4/mo
www.icloud.com
Other
Optional
Execution 116ms
Transfer 88 KB
Unused 74%
Monthly Cost $2/mo
www.icloud.com
Other
Optional
Execution 96ms
Transfer 47 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • www.icloud.com adds 1596ms and costs ~$21/month
  • Unattributable adds 362ms and costs ~$5/month
  • www.icloud.com adds 270ms and costs ~$4/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 1596ms 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

Unattributable takes 362ms 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

www.icloud.com takes 270ms 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

74% 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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