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

Accessibility

Best Practices

100

SEO

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

2.32 s

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

4.05 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

82 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.

2.32 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.

5.10 s

Page Load Progression

397 ms

794 ms

1.2 s

1.6 s

2.0 s

2.4 s

2.8 s

3.2 s

Checks

20 PASS 3 REVIEW

JS Execution Cost

Action

1494ms total JS execution

REVIEW

1494ms total JS execution

https://veo4-video.art/assets/framework-DJH1pfSr.j...: 579ms CPU time

https://veo4-video.art/: 569ms CPU time

Unattributable: 347ms CPU time

Main Thread Breakdown

Script Evaluation 33% Other 32% Style & Layout 25% Rendering 3% Parse HTML & CSS 3%

Script	Total	Scripting	Parse/Compile	Party
https://veo4-video.art/assets/framework-DJH1pfSr.js	579ms	468ms	0ms	1st
https://veo4-video.art/	569ms	21ms	34ms	1st
Unattributable	347ms	35ms	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.

HTTP Caching

public, max-age=0, s-maxage=60, must-revalidate

REVIEW

public, max-age=0, s-maxage=60, must-revalidate

Cache-Control header is set

Got: public, max-age=0, s-maxage=60, must-revalidate

CDN TTL: 1 minute (s-maxage=60)

No ETag or Last-Modified header

Conditional requests (304 Not Modified) are not possible without validators.

Cache-Control

public, max-age=0, s-maxage=60, must-revalidate

Directive	Value	Meaning
public	—	Any cache may store this response
max-age	0	Cache for 0 seconds
s-maxage	60	CDN caches for 1 minute
must-revalidate	—	Must recheck with server after expiry

A+

Page Weight Budget

425 KB transferred, 82 requests

PASS

425 KB transferred, 82 requests

Page weighs 1.3 MB (425 KB transferred)

82 HTTP requests

Estimated 0.09 g CO2 per page load

425 KB transferred

82 requests

0.09 g CO2 per page load

JavaScript 273.6 KiB 64%

HTML 48.4 KiB 11%

CSS 32.1 KiB 8%

Images 27.3 KiB 6%

Fonts 20.7 KiB 5%

Other 18.4 KiB 4%

Other 3.9 KiB 1%

Other 930 B 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Under budget

A+

Third-Party Impact

1% third-party, 0 ms blocking

PASS

1% third-party, 0 ms blocking

Third-party code accounts for 1% of page weight (6.2 KiB of 425.2 KiB)

Third-party blocking time is low (0 ms)

99%

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

3 images, 0 KB saveable

PASS

3 images, 0 KB saveable

All images are well-optimized

3 images 27 KB

0 oversized -0 KB

1 legacy format

0 missing dimensions CLS risk

A+

Font Loading

2 fonts (21 KB)

PASS

2 fonts (21 KB)

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

Web fonts

21 KB total

Render-blocking

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

outfit-19c86109.woff2 woff2 swap

Size 7 KB

Load time 30 ms

Start 90 ms

Risk FOUT — text flashes from fallback to web font

outfit-be21ba2a.woff2 woff2 swap

Size 14 KB

Load time 30 ms

Start 91 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)

A+

JS Bundles

64 scripts, 0 KB unused

PASS

64 scripts, 0 KB unused

0 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://veo4-video.art/assets/global-error-CVl8f3Cz.js	1 KB	—	✓	1st
https://veo4-video.art/assets/framework-DJH1pfSr.js	60 KB	—	✓	1st
https://veo4-video.art/assets/rolldown-runtime-QTnfLwEv.js	1 KB	—	✓	1st
https://veo4-video.art/assets/url-utils-BQKFb685.js	1 KB	—	✓	1st
https://veo4-video.art/assets/error-vu_n7QCq.js	1 KB	—	✓	1st
https://veo4-video.art/assets/navigation-DzNlvf1v.js	1 KB	—	✓	1st
https://veo4-video.art/assets/react-DlbkFqaW.js	13 KB	—	✓	1st
https://veo4-video.art/assets/BaseLink-D82kve3f.js	6 KB	—	✓	1st
https://veo4-video.art/assets/locale-C4W5Hkep.js	2 KB	—	✓	1st
https://veo4-video.art/assets/welcome-copy-DIyE0o41.js	2 KB	—	✓	1st

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

4 hints, 0 missing preconnects

PASS

4 hints, 0 missing preconnects

Page uses 4 resource hint(s)

Current Resource Hints

preconnect

—

preload

dns-prefetch

—

prefetch

—

4 resource hints configured

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, s-maxage=60, must-revalidate

A+

Server Response Intelligence

2 server-response signal(s) detected

PASS

2 server-response signal(s) detected

`Vary` header declared: RSC, Accept, Next-Router-State-Tree, Next-Router-Prefetch, Next-Router-Segment-P...

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).

No `ETag` or `Last-Modified` -- conditional GET not supported

Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.

A+

Page Weight Inventory

82 resources · 425 KB · 0 KB savings available

PASS

82 resources · 425 KB · 0 KB savings available

Within 1MB page-weight target

Got: 425 KB

7 third-party resources (1% of weight)

82 resources · 425.2 KiB · 7 third-party Within 1MB page-weight target

JavaScript 64% · 273.6 KiB

Document 11% · 48.4 KiB

Image 11% · 45.7 KiB

CSS 8% · 32.1 KiB

Font 5% · 20.7 KiB

Other 1% · 4.8 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

82 resources			425.2 KiB

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

A+

JavaScript Blocking

No render-blocking JS or document.write usage detected

PASS

No render-blocking JS or document.write usage detected

No JavaScript blocking issues detected

CSS Performance Depth

1 CSS depth issue(s) detected

PASS

1 CSS depth issue(s) detected

1 `@font-face` rule(s) without `font-display` -- causes FOIT

An `@font-face` rule without `font-display` causes Flash of Invisible Text (FOIT): the browser hides the styled text for up to 3 seconds while the custom font downloads, then either swaps to fallback (Chrome / Firefox) or stays invisible (older Safari). Add `font-display: swap` (shows fallback immediately, swaps in the custom font when ready) or `font-display: optional` (uses fallback if the font isn't ready in 100ms; never causes visible swap). Either eliminates FOIT outright.

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

82 requests over 868ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Image Optimization

4 images, 28 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

28 KB

1 missing lazy loading

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