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https://hstspreload.org

Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
95
GRADE
A
FIX
1
REVIEW
4
PASS
18
INFO
3

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.
97
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.
90
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.

1.11 s

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

1.11 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.

0.000

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

1.50 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.

1.11 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
26
18 PASS 4 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.
Info::
Last-Modified header present

No Cache-Control header

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

B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
B
Document Compression
Document response uses gzip; brotli would be ~20% smaller
REVIEW
Document response uses gzip; brotli would be ~20% smaller
Info::
Main HTML response uses gzip (brotli would be ~20% smaller)
All current browsers support brotli. Most CDNs (Cloudflare, Fastly, AWS CloudFront, Vercel, Netlify) can switch from gzip to brotli with a single config flag. Origin servers (nginx, Apache) need a brotli module compiled in -- nginx-brotli or Apache mod_brotli.
B
Main HTML Cache-Control
No Cache-Control header on main HTML response
REVIEW
No Cache-Control header on main HTML response
Info::
Main HTML response has no Cache-Control header
Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.
B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
A+
Page Weight Budget
19 KB transferred, 8 requests
PASS
19 KB transferred, 8 requests
Info::
Page weighs 44 KB (19 KB transferred)
Info::
8 HTTP requests
Info::
Estimated 0.00 g CO2 per page load
19 KB / 2.4 MB budget
19 KB transferred
8 requests
0.00 g CO2 per page load
HTML 6.1 KiB 32%
Other 5.4 KiB 28%
JavaScript 4.9 KiB 26%
CSS 2.7 KiB 14%
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
No images on this page
PASS
No images on this page
Info::
No images on this page
0 images 0 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+
JS Execution Cost
327ms total JS execution
PASS
327ms total JS execution
Info::
https://hstspreload.org/: 190ms CPU time
Info::
Unattributable: 137ms CPU time

Main Thread Breakdown

Other 45% Style & Layout 36% Script Evaluation 8% Rendering 5% Parse HTML & CSS 5%
ScriptTotalScriptingParse/CompileParty
https://hstspreload.org/190ms12ms2ms1st
Unattributable137ms9ms0ms1st
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
3 scripts, 0 KB unused
PASS
3 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://hstspreload.org/static/js/base.js1 KB—✓1st
https://hstspreload.org/static/js/view.js2 KB—✓1st
https://hstspreload.org/static/js/form.js2 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+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+
Server Response Intelligence
2 server-response signal(s) detected
PASS
2 server-response signal(s) detected
Info::
`Vary` header declared: Accept-Encoding
The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).
Info::
`Last-Modified` present -- timestamp-based conditional GET supported
Consider also setting `ETag` for stronger revalidation -- ETags are content hashes that don't suffer from clock-skew or DST issues. Last-Modified alone is functional for conditional GETs and not a bug.
A+
Page Weight Inventory
8 resources · 19 KB · 0 KB savings available
PASS
8 resources · 19 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 19 KB
8 resources · 19.1 KiB · 0 third-party Within 1MB page-weight target
Document 32% · 6.1 KiB
Image 28% · 5.4 KiB
JavaScript 26% · 4.9 KiB
CSS 14% · 2.7 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
JavaScript Blocking
1 JS blocking issue(s) detected
PASS
1 JS blocking issue(s) detected
Warning::
3 render-blocking <script src> tag(s) without async/defer
Each `<script src=...>` without `async`, `defer`, or `type="module"` blocks HTML parsing while the browser fetches and executes it. The block lasts the entire round-trip + execution time -- on slow networks this translates directly into LCP delay. Add `defer` (executes after parse, in source order) for scripts that interact with the DOM, or `async` (executes whenever ready) for analytics / independent scripts. Module scripts (`type="module"`) are deferred by default.
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
No CSS performance depth issues 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: Google Cloud

Asset Compression
No text asset hosts to measure
INFO
No text asset hosts to measure
Info::
No third-party or subdomain host served enough text assets to measure
Asset compression is measured per host, from one HEAD request against a sampled resource. Pages that serve all their JS and CSS from the document's own origin are covered by the document compression check instead.
Network Waterfall
8 requests over 971ms
INFO
0 ms 500 ms 1.0 s FCP 1.1 s LCP 1.1 shttps://hstspreload.org// https://hstspreload.org/ — 200 — 6.1 KiB — 243 ms — h2https://hstspreload.org/static/css/style.css/static/css/style.css https://hstspreload.org/static/css/style.css — 200 — 949 B — 227 ms — h2https://hstspreload.org/static/css/form.css/static/css/form.css https://hstspreload.org/static/css/form.css — 200 — 695 B — 222 ms — h2https://hstspreload.org/static/css/github.css/static/css/github.css https://hstspreload.org/static/css/github.css — 200 — 1.1 KiB — 151 ms — h2https://hstspreload.org/static/js/base.js/static/js/base.js https://hstspreload.org/static/js/base.js — 200 — 924 B — 226 ms — h2https://hstspreload.org/static/js/view.js/static/js/view.js https://hstspreload.org/static/js/view.js — 200 — 1.6 KiB — 245 ms — h2https://hstspreload.org/static/js/form.js/static/js/form.js https://hstspreload.org/static/js/form.js — 200 — 2.4 KiB — 234 ms — h2https://hstspreload.org/favicon.ico/favicon.ico https://hstspreload.org/favicon.ico — 200 — 5.4 KiB — 236 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Real-User Performance (CrUX)
Field metrics from the Chrome User Experience Report
INFO

Chrome User Experience (CrUX)

Real-user metrics from the Chrome UX Report (2026-09-16 — 2026-10-13)

LCP (p75)

1048 ms

96% good

INP (p75)

47 ms

93% good

CLS (p75)

0.050

92% good

FCP (p75)

1024 ms

TTFB (p75)

663 ms

This origin passes Core Web Vitals assessment
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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