Performance

· 22 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.

955 ms

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

1.16 s

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

2 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.071

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

955 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.

1.19 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

16 PASS 3 REVIEW

JS Bundles

9 scripts, 148 KB unused

REVIEW

9 scripts, 148 KB unused

https://ai-tooluniverse.com/assets/vendor-firebase...: 118 KB unused (71%)

Consider code splitting or tree shaking to reduce unused code.

https://ai-tooluniverse.com/assets/vendor-react-BZ...: 30 KB unused (47%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 148 KB

148 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://ai-tooluniverse.com/assets/vendor-firebase-CK2y1gyF.js	167 KB	118 KB (71%)	✓	1st
https://ai-tooluniverse.com/assets/vendor-react-BZaxmVD2.js	65 KB	30 KB (47%)	✓	1st
https://ai-tooluniverse.com/assets/index-DPakabBY.js	72 KB	—	✓	1st
https://ai-tooluniverse.com/assets/rolldown-runtime-XKyaHtl9.js	1 KB	—	✓	1st
https://ai-tooluniverse.com/assets/vendor-icons--AjIoFsD.js	11 KB	—	✓	1st
https://ai-tooluniverse.com/assets/AuthContext-B3O5OA_K.js	3 KB	—	✓	1st
https://ai-tooluniverse.com/assets/AuthModal-B1JwRszz.js	4 KB	—	✓	1st
https://ai-tooluniverse.com/cdn-cgi/challenge-platform/h/b/scripts/jsd/f8df4d4a0cd6/main.js?ray=a5a2e8d3bc89565a	17 KB	—	✓	1st
https://ai-tooluniverse.com/assets/UpgradeModal-hyo_cZi-.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

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

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, must-revalidate

REVIEW

public, max-age=0, must-revalidate

Cache-Control header is set

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

No ETag or Last-Modified header

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

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+

Page Weight Budget

449 KB transferred, 27 requests

PASS

449 KB transferred, 27 requests

Page weighs 1.4 MB (449 KB transferred)

27 HTTP requests

Estimated 0.09 g CO2 per page load

449 KB transferred

27 requests

0.09 g CO2 per page load

JavaScript 341.0 KiB 76%

Other 57.0 KiB 13%

Fonts 26.7 KiB 6%

CSS 18.6 KiB 4%

HTML 2.0 KiB 0%

Other 1.3 KiB 0%

Other 1.1 KiB 0%

Other 1.0 KiB 0%

0 2.4 MB 4.9 MB

Under budget

A+

Third-Party Impact

6% third-party, 0 ms blocking

PASS

6% third-party, 0 ms blocking

Third-party code accounts for 6% of page weight (29.0 KiB of 448.7 KiB)

Third-party blocking time is low (0 ms)

94%

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

No images on this page

PASS

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

497ms total JS execution

PASS

497ms total JS execution

https://ai-tooluniverse.com/: 168ms CPU time

Unattributable: 133ms CPU time

https://ai-tooluniverse.com/cdn-cgi/challenge-plat...: 106ms CPU time

https://ai-tooluniverse.com/assets/vendor-react-BZ...: 90ms CPU time

Main Thread Breakdown

Script Evaluation 43% Other 27% Style & Layout 21% Garbage Collection 5% Rendering 4%

Script	Total	Scripting	Parse/Compile	Party
https://ai-tooluniverse.com/	168ms	20ms	0ms	1st
Unattributable	133ms	4ms	0ms	1st
https://ai-tooluniverse.com/cdn-cgi/challenge-platform/scripts/jsd/main.js?ray=a5a2e8d3bc89565a	106ms	96ms	1ms	1st
https://ai-tooluniverse.com/assets/vendor-react-BZaxmVD2.js	90ms	79ms	0ms	1st

A+

Font Loading

1 fonts (27 KB)

PASS

1 fonts (27 KB)

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

Web fonts

27 KB total

Render-blocking

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

LDIoaomQNQcsA88c7O9yZ4K... woff2 swap

Size 27 KB

Load time 30 ms

Start 336 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+

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

A+

Server Response Intelligence

2 server-response signal(s) detected

PASS

2 server-response signal(s) detected

`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).

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

27 resources · 449 KB · 148 KB savings available

PASS

27 resources · 449 KB · 148 KB savings available

Within 1MB page-weight target

Got: 449 KB

~148 KB of savings available

8 third-party resources (6% of weight)

27 resources · 448.7 KiB · 8 third-party Within 1MB page-weight target

JavaScript 76% · 341.0 KiB

Other 13% · 59.4 KiB

Font 6% · 26.7 KiB

CSS 4% · 18.6 KiB

Document 0% · 2.0 KiB

Image 0% · 1.0 KiB

~147.6 KiB of savings available

Remove unused JavaScript: 147.6 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

27 resources			448.7 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

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

27 requests over 26664ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Image Optimization

1 images, 3 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

3 KB

1 missing dimensions 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.