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https://semver.org

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
100
GRADE
A+
FIX
0
REVIEW
1
PASS
14
INFO
2

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

Mobile Desktop
100
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
65
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.
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.

887 ms

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

887 ms

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.

0.000

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

887 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.

887 ms

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
14 PASS 1 REVIEW
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
58 KB transferred, 5 requests
PASS
58 KB transferred, 5 requests
Info::
Page weighs 82 KB (58 KB transferred)
Info::
5 HTTP requests
Info::
Estimated 0.01 g CO2 per page load
58 KB / 2.4 MB budget
58 KB transferred
5 requests
0.01 g CO2 per page load
Other 45.8 KiB 80%
HTML 9.3 KiB 16%
CSS 1.9 KiB 3%
JavaScript 580 B 1%
Images 0 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+
Image Optimization
1 images, 0 KB saveable
PASS
1 images, 0 KB saveable
Info::
All images are well-optimized
1 images 0 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+
JS Execution Cost
292ms total JS execution
PASS
292ms total JS execution
Info::
https://semver.org/: 184ms CPU time
Info::
Unattributable: 108ms CPU time
Info::
Third-party scripts: 108ms (37% of total)

Main Thread Breakdown

Style & Layout 43% Other 38% Rendering 9% Script Evaluation 7%
ScriptTotalScriptingParse/CompileParty
https://semver.org/184ms4ms1ms1st
Unattributable108ms10ms0ms3rd
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, 0 KB unused
PASS
1 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://semver.org/js/anchorli.js1 KB—✓1st
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
5 resources · 58 KB · 0 KB savings available
PASS
5 resources · 58 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 58 KB
Info::
1 third-party resources (0% of weight)
5 resources · 57.6 KiB · 1 third-party Within 1MB page-weight target
Image 80% · 45.8 KiB
Document 16% · 9.3 KiB
CSS 3% · 1.9 KiB
JavaScript 1% · 580 B
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=600 (10 minutes)
PASS
max-age=600 (10 minutes)
Info::
Cache-Control header is set
Got: max-age=600
Info::
Effective TTL: 10 minutes (max-age=600)
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present
Cache-Control

max-age=600

DirectiveValueMeaning
max-age600Cache for 10 minutes
Effective TTL: 600 seconds
Network Waterfall
5 requests over 293ms
INFO
0 ms 200 ms 400 ms 600 ms 800 ms FCP 887 ms LCP 887 mshttps://semver.org// https://semver.org/ — 200 — 9.3 KiB — 182 ms — h2https://semver.org/css/main.css/css/main.css https://semver.org/css/main.css — 200 — 1.9 KiB — 31 ms — h2https://semver.org/js/anchorli.js/js/anchorli.js https://semver.org/js/anchorli.js — 200 — 580 B — 27 ms — h2data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiIHN0YW5kYWxvbmU9Im5vIj8+C…data:image/svg+xml;base64,PD94bWwgd... data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiIHN0YW5kYWxvbmU9Im5vIj8+C… — 200 — 0 B — 0 ms — datahttps://semver.org/assets/500x500(dark).jpg/assets/500x500(dark).jpg https://semver.org/assets/500x500(dark).jpg — 200 — 45.8 KiB — 18 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
37% of JavaScript execution is third-party
First-party Third-party 108ms · 0KB · $0/mo
Unattributable
Other
Optional
Execution 108ms
Transfer 0 KB
Monthly Cost $0/mo

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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