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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
98
GRADE
A+
FIX
1
REVIEW
1
PASS
11
INFO
1

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.
83
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.

242 ms

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

242 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.

0.001

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

662 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.

242 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
14
11 PASS 1 REVIEW 1 FIX
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

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

Green Hosting

No green hosting detected

A+
Page Weight Budget
264 KB transferred, 5 requests
PASS
264 KB transferred, 5 requests
Info::
Page weighs 279 KB (264 KB transferred)
Info::
5 HTTP requests
Info::
Estimated 0.05 g CO2 per page load
264 KB / 2.4 MB budget
264 KB transferred
5 requests
0.05 g CO2 per page load
Images 255.5 KiB 97%
HTML 6.1 KiB 2%
CSS 1.5 KiB 1%
Other 1.4 KiB 1%
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
2 images, 0 KB saveable
PASS
2 images, 0 KB saveable
Warning::
https://llvm.org/img/LLVMWyvernSmall.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
2 images 255 KB
0 oversized -0 KB
2 legacy format
1 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

A+
JS Execution Cost
67ms total JS execution
PASS
67ms total JS execution
Info::
https://llvm.org/: 67ms CPU time

Main Thread Breakdown

Other 46% Style & Layout 35% Rendering 12% Script Evaluation 4%
ScriptTotalScriptingParse/CompileParty
https://llvm.org/67ms2ms0ms1st
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
No JavaScript
PASS
No JavaScript
Info::
No JavaScript bundles
No JavaScript files loaded.
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 · 264 KB · 0 KB savings available
PASS
5 resources · 264 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 264 KB
Info::
1 resources over 200KB
5 resources · 264.5 KiB · 0 third-party Within 1MB page-weight target
Image 97% · 256.9 KiB
Document 2% · 6.1 KiB
CSS 1% · 1.5 KiB
Network Waterfall
5 requests over 2119ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s FCP 242 ms LCP 242 mshttps://llvm.org// https://llvm.org/ — 200 — 6.1 KiB — 603 ms — http/1.1https://llvm.org/llvm.css/llvm.css https://llvm.org/llvm.css — 200 — 1.5 KiB — 152 ms — http/1.1https://llvm.org/img/LLVMWyvernSmall.png/img/LLVMWyvernSmall.png https://llvm.org/img/LLVMWyvernSmall.png — 200 — 255.2 KiB — 1.0 s — http/1.1https://llvm.org/img/lines.gif/img/lines.gif https://llvm.org/img/lines.gif — 200 — 336 B — 446 ms — http/1.1https://llvm.org/favicon.ico/favicon.ico https://llvm.org/favicon.ico — 200 — 1.4 KiB — 449 ms — http/1.1
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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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