Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

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

Mobile Desktop

Performance

100

Accessibility

Best Practices

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

3.36 s

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

12.14 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.

4.72 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.

12.14 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

18 PASS 5 REVIEW

Page Weight Budget

Action

2.0 MB transferred, 63 requests

REVIEW

2.0 MB transferred, 63 requests

Page weighs 3.9 MB (2.0 MB transferred)

63 HTTP requests

Estimated 0.41 g CO2 per page load

2.0 MB transferred

63 requests

0.41 g CO2 per page load

Other 1.6 MiB 83%

Fonts 172.3 KiB 9%

JavaScript 120.9 KiB 6%

CSS 40.0 KiB 2%

Other 6.8 KiB 0%

HTML 3.1 KiB 0%

Other 0 B 0%

Images 0 B 0%

0 2.4 MB 4.9 MB

Approaching limit

JS Execution Cost

950ms total JS execution

REVIEW

950ms total JS execution

Unattributable: 472ms CPU time

https://racing-hub.pages.dev/: 242ms CPU time

https://racing-hub.pages.dev/js/modules/newsModule...: 130ms CPU time

https://racing-hub.pages.dev/js/app.js: 107ms CPU time

Main Thread Breakdown

Other 53% Style & Layout 22% Script Evaluation 15% Rendering 4% Parse HTML & CSS 4%

Script	Total	Scripting	Parse/Compile	Party
Unattributable	472ms	7ms	0ms	1st
https://racing-hub.pages.dev/	242ms	4ms	1ms	1st
https://racing-hub.pages.dev/js/modules/newsModule.js	130ms	100ms	0ms	1st
https://racing-hub.pages.dev/js/app.js	107ms	36ms	0ms	1st

Server-Timing Observability

No Server-Timing header found

REVIEW

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.

Page Weight Inventory

Action

63 resources · 2.0 MB · 43 KB savings available

REVIEW

63 resources · 2.0 MB · 43 KB savings available

Page weight 2.0 MB exceeds 1 MB target by 975 KB

Got: 2.0 MB Expected: ≤ 1 MB

31 third-party resources (13% of weight)

1 resources over 200KB

63 resources · 2.0 MiB · 31 third-party 975.5 KiB over 1MB target

Image 83% · 1.6 MiB

Font 9% · 172.3 KiB

JavaScript 6% · 120.9 KiB

CSS 2% · 40.0 KiB

Other 0% · 6.8 KiB

Document 0% · 3.1 KiB

~43.3 KiB of savings available

Remove unused JavaScript: 43.3 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

63 resources			2.0 MiB

HTTP Caching

public, max-age=0, must-revalidate

REVIEW

public, max-age=0, must-revalidate

Cache-Control header is set

Got: public, max-age=0, must-revalidate

ETag present — enables conditional (304) responses

Cache-Control

public, max-age=0, must-revalidate

Directive	Value	Meaning
public	—	Any cache may store this response
max-age	0	Cache for 0 seconds
must-revalidate	—	Must recheck with server after expiry

A+

Third-Party Impact

13% third-party, 0 ms blocking

PASS

13% third-party, 0 ms blocking

Third-party code accounts for 13% of page weight (252.9 KiB of 2.0 MiB)

Third-party blocking time is low (0 ms)

87%

First-party Third-party

A+

Text Compression

All text resources are compressed

PASS

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

All images are well-optimized

1 images 0 KB

0 oversized -0 KB

0 legacy format

0 missing dimensions CLS risk

A+

Font Loading

2 fonts (172 KB)

PASS

2 fonts (172 KB)

2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

172 KB total

Render-blocking

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

fa-solid-900.woff2 woff2 swap

Size 147 KB

Load time 57 ms

Start 409 ms

Risk FOUT — text flashes from fallback to web font

Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need

fa-regular-400.woff2 woff2 swap

Size 25 KB

Load time 45 ms

Start 818 ms

Risk FOUT — text flashes from fallback to web font

Optimization checklist

Preload critical fonts (priority=high)
Use woff2 format for all fonts
Set font-display to swap, optional, or fallback
Subset large fonts (≤100 KB each)

Fixing the unchecked items could save ~74 KB and ~148 ms

A+

JS Bundles

17 scripts, 43 KB unused

PASS

17 scripts, 43 KB unused

https://cdn.jsdelivr.net/npm/@supabase/supabase-js...: 43 KB unused (80%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 43 KB

43 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://cdn.jsdelivr.net/npm/@supabase/supabase-js@2.115.0/dist/umd/supabase.min.js	55 KB	43 KB (80%)	✓	3rd
https://racing-hub.pages.dev/js/app.js	3 KB	—	✓	1st
https://racing-hub.pages.dev/js/store.js	4 KB	—	✓	1st
https://racing-hub.pages.dev/js/i18n.js	12 KB	—	✓	1st
https://racing-hub.pages.dev/js/modules/newsModule.js	5 KB	—	✓	1st
https://racing-hub.pages.dev/js/modules/statsModule.js	9 KB	—	✓	1st
https://racing-hub.pages.dev/js/modules/pronosticsModule.js	4 KB	—	✓	1st
https://racing-hub.pages.dev/js/modules/quizModule.js	3 KB	—	✓	1st
https://racing-hub.pages.dev/js/modules/gamificationModule.js	5 KB	—	✓	1st
https://racing-hub.pages.dev/js/modules/collectionModule.js	1 KB	—	✓	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

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

A+

Resource Hints

No optimization needed

PASS

No optimization needed

No resource hint issues

A+

HTTP/3 (QUIC)

HTTP/3 advertised via Alt-Svc

PASS

HTTP/3 advertised via Alt-Svc

HTTP/3 (QUIC) is supported

First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.

A+

Document Compression

Document response uses brotli

PASS

Document response uses brotli

Main HTML response uses brotli (Content-Encoding: br)

Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.

A+

LCP Image Preload

LCP preload audit not available

PASS

LCP preload audit not available

LCP image preload audit not available for this scan

A+

Main HTML Cache-Control

Main HTML max-age=0 (≤ 5min) is appropriate

PASS

Main HTML max-age=0 (≤ 5min) is appropriate

Got: public, max-age=0, must-revalidate

Server Response Intelligence

2 server-response signal(s) detected

PASS

2 server-response signal(s) detected

Compressed response missing `Vary` header

The page is served with `Content-Encoding: br` but has no `Vary` header. Without `Vary: Accept-Encoding`, intermediary caches (corporate proxies, ISP caches) may serve the compressed variant to clients that didn't send the matching `Accept-Encoding` -- the client sees garbled bytes. Add `Vary: Accept-Encoding` whenever the response is conditionally compressed.

`ETag` present -- conditional GET supported

A+

Render-Blocking Resources

No render-blocking resources detected

PASS

No render-blocking resources detected

No render-blocking resources detected in <head>

A+

Third-Party Resources

No third-party resources detected

PASS

No third-party resources detected

JavaScript Blocking

1 JS blocking issue(s) detected

PASS

1 JS blocking issue(s) detected

1 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.

CSS Performance Depth

1 CSS depth issue(s) detected

PASS

1 CSS depth issue(s) detected

14 render-blocking stylesheet(s) -- recommended: <=3

Each `<link rel="stylesheet">` without a non-blocking `media` attribute holds up the first paint. Browsers download all of them before painting any content. Consolidate into 1-2 critical-path stylesheets; defer non-critical CSS via `<link rel="stylesheet" media="print" onload="this.media='all'">` or via the loadCSS pattern; inline above-the-fold CSS in `<style>` to short-circuit the request entirely.

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

Asset Compression

No text asset hosts to measure

INFO

No text asset hosts to measure

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

63 requests over 862ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Image Optimization

26 images, 0 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

0 KB

Oversized

26 missing dimensions 26 missing lazy loading

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.