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https://jigsaw.w3.org

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
98
GRADE
A+
FIX
0
REVIEW
1
PASS
12
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.
81
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.
92
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.

354 ms

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

354 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.

0.027

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

354 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.

354 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
12 PASS 1 REVIEW
B
Image Optimization
2 images, 0 KB saveable
REVIEW
2 images, 0 KB saveable
Warning::
https://jigsaw.w3.org/icons/jigsaw.gif is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jigsaw.w3.org/icons/jigpower.gif is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
2 images 5 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

A+
Page Weight Budget
8 KB transferred, 4 requests
PASS
8 KB transferred, 4 requests
Info::
Page weighs 10 KB (8 KB transferred)
Info::
4 HTTP requests
Info::
Estimated 0.00 g CO2 per page load
8 KB / 2.4 MB budget
8 KB transferred
4 requests
0.00 g CO2 per page load
Images 5.2 KiB 64%
HTML 2.5 KiB 32%
Other 358 B 4%
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
No JS execution data
PASS
No JS execution data
Info::
No significant JS execution detected

Main Thread Breakdown

Other 54% Style & Layout 30% Rendering 7% Script Evaluation 6%
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
4 resources · 8 KB · 0 KB savings available
PASS
4 resources · 8 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 8 KB
4 resources · 8.1 KiB · 0 third-party Within 1MB page-weight target
Image 68% · 5.5 KiB
Document 32% · 2.5 KiB
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

A+
HTTP Caching
max-age=86400 (1 day)
PASS
max-age=86400 (1 day)
Info::
Cache-Control header is set
Got: max-age=86400
Info::
Effective TTL: 1 day (max-age=86400)
Info::
Last-Modified header present
Cache-Control

max-age=86400

DirectiveValueMeaning
max-age86400Cache for 1 day
Effective TTL: 86400 seconds
Network Waterfall
4 requests over 353ms
INFO
0 ms 200 ms FCP 354 ms LCP 354 mshttps://jigsaw.w3.org// https://jigsaw.w3.org/ — 200 — 2.5 KiB — 162 ms — h3https://jigsaw.w3.org/icons/jigsaw.gif/icons/jigsaw.gif https://jigsaw.w3.org/icons/jigsaw.gif — 200 — 2.1 KiB — 154 ms — h3https://jigsaw.w3.org/icons/jigpower.gif/icons/jigpower.gif https://jigsaw.w3.org/icons/jigpower.gif — 200 — 3.1 KiB — 155 ms — h3https://jigsaw.w3.org/favicon.ico/favicon.ico https://jigsaw.w3.org/favicon.ico — 200 — 358 B — 17 ms — h3
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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