Performance

· 27 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

100

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.

2.00 s

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

6.44 s

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

279 ms

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

0.005

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

2.49 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.

6.48 s

Page Load Progression

1.1 s

2.2 s

3.3 s

4.3 s

5.4 s

6.5 s

7.6 s

8.7 s

Checks

19 PASS 3 REVIEW 1 FIX

JS Execution Cost

Action

2527ms total JS execution

FIX

2527ms total JS execution

https://stocktostove.com/: 1418ms CPU time

Unattributable: 550ms CPU time

https://www.googletagmanager.com/gtag/js?id=G-XE1F...: 465ms CPU time

https://static.cloudflareinsights.com/beacon.min.j...: 94ms CPU time

Third-party scripts: 559ms (22% of total)

Main Thread Breakdown

Other 44% Script Evaluation 24% Style & Layout 17% Rendering 9% Script Parsing & Compilation 4%

Script	Total	Scripting	Parse/Compile	Party
https://stocktostove.com/	1418ms	48ms	11ms	1st
Unattributable	550ms	65ms	0ms	1st
https://www.googletagmanager.com/gtag/js?id=G-XE1FVB6MSP	465ms	371ms	90ms	3rd
https://static.cloudflareinsights.com/beacon.min.js/v31edd6df95cf4e85bb4c19e7a9bdbcba1788362987495	94ms	75ms	0ms	3rd

JS Bundles

4 scripts, 73 KB unused

REVIEW

4 scripts, 73 KB unused

https://www.googletagmanager.com/gtag/js?id=G-XE1F...: 73 KB unused (42%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 73 KB

73 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://www.googletagmanager.com/gtag/js?id=G-XE1FVB6MSP	171 KB	73 KB (42%)	✓	3rd
https://stocktostove.com/_astro/page.DDsIKVU2.js	2 KB	—	✓	1st
https://stocktostove.com/_astro/IngredientPicker.astro_astro_type_script_index_0_lang.CW-bq8Jk.js	4 KB	—	✓	1st
https://static.cloudflareinsights.com/beacon.min.js/v31edd6df95cf4e85bb4c19e7a9bdbcba1788362987495	10 KB	—	✓	3rd

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

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

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

673 KB transferred, 28 requests

PASS

673 KB transferred, 28 requests

Page weighs 1.3 MB (673 KB transferred)

28 HTTP requests

Estimated 0.14 g CO2 per page load

673 KB transferred

28 requests

0.14 g CO2 per page load

Images 326.5 KiB 49%

JavaScript 187.4 KiB 28%

Other 69.3 KiB 10%

Fonts 52.4 KiB 8%

HTML 15.9 KiB 2%

CSS 11.4 KiB 2%

Other 9.9 KiB 1%

Other 471 B 0%

0 2.4 MB 4.9 MB

Under budget

Third-Party Impact

27% third-party, 0 ms blocking

PASS

27% third-party, 0 ms blocking

Third-party code accounts for 27% of page weight (181.7 KiB of 673.2 KiB)

Third-party blocking time is low (0 ms)

73%

27%

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

14 images, 0 KB saveable

PASS

14 images, 0 KB saveable

All images are well-optimized

14 images 327 KB

0 oversized -0 KB

0 legacy format

0 missing dimensions CLS risk

A+

Font Loading

2 fonts (52 KB)

PASS

2 fonts (52 KB)

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

Web fonts

52 KB total

Render-blocking

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

502b9851e13aed9b.woff2 woff2 swap

Size 29 KB

Load time 32 ms

Start 116 ms

Risk FOUT — text flashes from fallback to web font

181a29443484632f.woff2 woff2 swap

Size 23 KB

Load time 21 ms

Start 203 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

2 hints, 0 missing preconnects

PASS

2 hints, 0 missing preconnects

Page uses 2 resource hint(s)

Current Resource Hints

preconnect

—

preload

dns-prefetch

—

prefetch

—

2 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, must-revalidate

A+

Server-Timing Observability

3 Server-Timing entries advertised

PASS

3 Server-Timing entries advertised

Server-Timing header advertises 3 timing entries

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.

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

28 resources · 673 KB · 73 KB savings available

PASS

28 resources · 673 KB · 73 KB savings available

Within 1MB page-weight target

Got: 673 KB

~73 KB of savings available

3 third-party resources (27% of weight)

28 resources · 673.2 KiB · 3 third-party Within 1MB page-weight target

Image 50% · 335.5 KiB

JavaScript 28% · 187.4 KiB

Other 10% · 69.7 KiB

Font 8% · 52.4 KiB

Document 3% · 16.9 KiB

CSS 2% · 11.4 KiB

~72.5 KiB of savings available

Remove unused JavaScript: 72.5 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

28 resources			673.2 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

A+

CSS Performance Depth

No CSS performance depth issues detected

PASS

No CSS performance depth issues detected

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

28 requests over 8288ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

22% of JavaScript execution is third-party

First-party Third-party 559ms · 181KB · €9/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
Google Tag Manager www.googletagmanager.com	Tag Manager	465ms	171 KB	42%	€7/mo	Costly
static.cloudflareinsights.com static.cloudflareinsights.com	Other	94ms	10 KB	—	€2/mo	Optional

Google Tag Manager

Tag Manager

Costly

Execution 465ms

Transfer 171 KB

Unused 42%

Monthly Cost €7/mo

static.cloudflareinsights.com

Other

Optional

Execution 94ms

Transfer 10 KB

Monthly Cost €2/mo

These scripts may cost more than they're worth

Google Tag Manager adds 465ms and costs ~€7/month

Google Tag Manager takes 465ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

How third-party costs are calculated

Image Optimization

13 images, 214 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

214 KB

4 missing lazy loading

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