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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
98
GRADE
A+
FIX
0
REVIEW
2
PASS
13
INFO
2

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

Mobile Desktop
83
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
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.

821 ms

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

1.74 s

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

0 ms

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

0.349

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

821 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.

1.74 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
17
13 PASS 2 REVIEW
B
Image Optimization
2 images, 0 KB saveable
REVIEW
2 images, 0 KB saveable
Warning::
https://getcomposer.org/img/logo-composer-transpar... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://getcomposer.org/img/private-packagist-logo... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
2 images 113 KB
0 oversized -0 KB
2 legacy format
2 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

B
HTTP Caching
no-cache, private
REVIEW
no-cache, private
Info::
Cache-Control header is set
Got: no-cache, private
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-cache, private

DirectiveValueMeaning
no-cache—Cache but always revalidate first
private—Only browser cache, not CDN/proxy
A+
Page Weight Budget
175 KB transferred, 7 requests
PASS
175 KB transferred, 7 requests
Info::
Page weighs 312 KB (175 KB transferred)
Info::
7 HTTP requests
Info::
Estimated 0.04 g CO2 per page load
175 KB / 2.4 MB budget
175 KB transferred
7 requests
0.04 g CO2 per page load
Images 112.9 KiB 65%
JavaScript 52.0 KiB 30%
CSS 5.6 KiB 3%
Other 2.5 KiB 1%
HTML 1.5 KiB 1%
Other 427 B 0%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
No third-party resources
PASS
No third-party resources
Info::
No third-party resources detected
No third-party resources detected — all resources are first-party.
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+
JS Execution Cost
194ms total JS execution
PASS
194ms total JS execution
Info::
Unattributable: 84ms CPU time
Info::
https://getcomposer.org/: 59ms CPU time
Info::
https://getcomposer.org/build/app.js?v=3: 52ms CPU time
Info::
Third-party scripts: 84ms (43% of total)

Main Thread Breakdown

Other 46% Style & Layout 21% Script Evaluation 21% Script Parsing & Compilation 7%
ScriptTotalScriptingParse/CompileParty
Unattributable84ms5ms0ms3rd
https://getcomposer.org/59ms3ms1ms1st
https://getcomposer.org/build/app.js?v=352ms31ms14ms1st
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+
JS Bundles
1 scripts, 40 KB unused
PASS
1 scripts, 40 KB unused
Warning::
https://getcomposer.org/build/app.js?v=3: 40 KB unused (78%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 40 KB
40 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://getcomposer.org/build/app.js?v=352 KB40 KB (78%)✓1st

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

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+
Page Weight Inventory
7 resources · 175 KB · 40 KB savings available
PASS
7 resources · 175 KB · 40 KB savings available
Info::
Within 1MB page-weight target
Got: 175 KB
7 resources · 175.0 KiB · 0 third-party Within 1MB page-weight target
Image 66% · 115.5 KiB
JavaScript 30% · 52.0 KiB
CSS 3% · 5.6 KiB
Document 1% · 1.5 KiB
Other 0% · 427 B

~40.3 KiB of savings available

Remove unused JavaScript: 40.3 KiB
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: OVHcloud

Network Waterfall
7 requests over 330ms
INFO
0 ms 500 ms 1.0 s 1.5 s FCP 821 ms LCP 1.7 shttps://getcomposer.org// https://getcomposer.org/ — 200 — 1.5 KiB — 71 ms — h2https://getcomposer.org/build/app.css?v=2/build/app.css?v=2 https://getcomposer.org/build/app.css?v=2 — 200 — 5.6 KiB — 23 ms — h2https://getcomposer.org/img/logo-composer-transparent3.png/img/logo-composer-transparent3.png https://getcomposer.org/img/logo-composer-transparent3.png — 200 — 107.4 KiB — 87 ms — h2https://getcomposer.org/img/private-packagist-logo-horizontal-2025.svg/img/private-packagist-logo-horizon... https://getcomposer.org/img/private-packagist-logo-horizontal-2025.svg — 200 — 5.6 KiB — 82 ms — h2https://getcomposer.org/build/app.js?v=3/build/app.js?v=3 https://getcomposer.org/build/app.js?v=3 — 200 — 52.0 KiB — 61 ms — h2https://getcomposer.org/api/event/api/event https://getcomposer.org/api/event — 202 — 427 B — 171 ms — h2https://getcomposer.org/favicon.ico/favicon.ico https://getcomposer.org/favicon.ico — 200 — 2.5 KiB — 85 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
43% of JavaScript execution is third-party
First-party Third-party 84ms · 0KB · €1/mo
Unattributable
Other
Optional
Execution 84ms
Transfer 0 KB
Monthly Cost €1/mo

43% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

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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