Browse & Analyze

Browse recent website audits and performance trends

Explore technology stacks detected across the web

Side-by-side technology comparisons and market share

Curated technology stacks and the sites that use them

Editorial deep-dives on the state of web performance

Browse and download favicons from analyzed websites

Learn

Common questions about BeaverCheck scores and checks

How we calculate scores across 100+ checks

The story behind BeaverCheck and the team

Practical guides to fix common web performance issues

Migration Guides

Step-by-step guides for moving between web technologies

Definitions for performance, SEO, and web platform terms

Contrast Checker

Check WCAG color contrast ratios between any two colors

Inspect HTTP response headers for any URL

Analyze SSL/TLS certificate details and chain

Look up DNS records for any domain

Redirect Checker

Trace the full redirect chain for any URL

Real-user INP and Core Web Vitals from Google's Chrome UX Report.

RESTful API for programmatic website audits

Embed an auto-updating health score badge on your site

https://rsf.org

Performance

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

SCORE

88

GRADE

B

FIX

1

REVIEW

4

PASS

8

INFO

2

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

88

Performance

93

Accessibility

96

Best Practices

92

SEO

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

734 ms

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

1.90 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.

0.091

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

1.29 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.

1.98 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

15

8 PASS 4 REVIEW 1 FIX

F

Page Weight Budget

Action

2.9 MB transferred, 58 requests

FIX

2.9 MB transferred, 58 requests

Page weighs 4.3 MB (2.9 MB transferred)

Images are 2.5 MB — compress or use modern formats

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Got: 2.5 MB

58 HTTP requests

Estimated 0.60 g CO2 per page load

2.9 MB transferred

58 requests

0.60 g CO2 per page load

Images 2.5 MiB 86%

JavaScript 213.1 KiB 7%

Fonts 91.9 KiB 3%

CSS 72.0 KiB 2%

HTML 21.1 KiB 1%

Other 3.4 KiB 0%

Other 692 B 0%

Other 35 B 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

B

Image Optimization

27 images, 0 KB saveable

REVIEW

27 images, 0 KB saveable

All images are well-optimized

27 images 2.5 MB

0 oversized -0 KB

27 legacy format

0 missing dimensions CLS risk

B

JS Bundles

12 scripts, 103 KB unused

REVIEW

12 scripts, 103 KB unused

https://cdn.jsdelivr.net/npm/chart.js@3.7.1: 42 KB unused (64%)

Consider code splitting or tree shaking to reduce unused code.

https://rsf.org/sites/default/files/js/js_Q8hR4-4X...: 35 KB unused (57%)

Consider code splitting or tree shaking to reduce unused code.

https://rsf.org/libraries/tarteaucitron/tarteaucit...: 25 KB unused (72%)

Consider code splitting or tree shaking to reduce unused code.

https://rsf.org/libraries/tarteaucitron/tarteaucit...: unminified — 10 KB could be saved

Total unused JavaScript: 103 KB

103 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://cdn.jsdelivr.net/npm/chart.js@3.7.1	66 KB	42 KB (64%)	✓	3rd
https://rsf.org/sites/default/files/js/js_Q8hR4-4XVzlJMxcyTvFTXSmfFqLE7IBzPksRejZaHZ4.js?scope=footer&delta=0&language=en&theme=rsf&include=eJwrKk7TT8_JT0rM0S0uqczJzEvXKSpOi0-tSEwuyczP009KLMrPTS0pSo1PzkgsKikGy5YkJusDMQDRrxed	63 KB	35 KB (57%)	✓	1st
https://rsf.org/libraries/tarteaucitron/tarteaucitron.services.js?v=20230203	35 KB	25 KB (72%)	✗	1st
https://rsf.org/cdn-cgi/scripts/7d0fa10a/cloudflare-static/rocket-loader.min.js	4 KB	—	✓	1st
https://static.cloudflareinsights.com/beacon.min.js	0 KB	—	✓	3rd
https://rsf.org/sites/default/files/js/js_wSowJaR7kDOqIhosxLwjQDwh4MX3o5S_PIEQDxyDRgc.js?scope=footer&delta=6&language=en&theme=rsf&include=eJwrKk7TT8_JT0rM0S0uqczJzEvXKSpOi0-tSEwuyczP009KLMrPTS0pSo1PzkgsKikGy5YkJusDMQDRrxed	1 KB	—	✓	1st
https://rsf.org/modules/custom/rsf_tac/js/tarteaucitron.services.js?v=1.4	2 KB	—	✓	1st
https://rsf.org/libraries/tarteaucitron/tarteaucitron.js?v=1.4	20 KB	—	✗	1st
https://rsf.org/sites/default/files/js/js_bPXo3Cc6Lnq-h2gLmwQciPwLnHAkVzQRa-8suTJSeCU.js?scope=footer&delta=3&language=en&theme=rsf&include=eJwrKk7TT8_JT0rM0S0uqczJzEvXKSpOi0-tSEwuyczP009KLMrPTS0pSo1PzkgsKikGy5YkJusDMQDRrxed	2 KB	—	✓	1st
https://rsf.org/themes/custom/rsf/assets/scripts/app.js?tbfu2i	9 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

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

C

Page Weight Inventory

Action

58 resources · 2.9 MB · 103 KB savings available

REVIEW

58 resources · 2.9 MB · 103 KB savings available

Page weight 1.9 MB over 1MB target

Got: 2.9 MB Expected: ≤ 1 MB

~103 KB of savings available

10 third-party resources (4% of weight)

1 resources over 200KB

58 resources · 2.9 MiB · 10 third-party 1.9 MiB over 1MB target

Image 86% · 2.5 MiB

JavaScript 7% · 213.1 KiB

Font 3% · 91.9 KiB

CSS 2% · 72.0 KiB

Document 1% · 21.7 KiB

Other 0% · 727 B

~102.6 KiB of savings available

Remove unused JavaScript: 102.6 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

58 resources			2.9 MiB

B

HTTP Caching

must-revalidate, no-cache, private

REVIEW

must-revalidate, no-cache, private

Cache-Control header is set

Got: must-revalidate, no-cache, private

No ETag or Last-Modified header

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

Cache-Control

must-revalidate, no-cache, private

Directive	Value	Meaning
must-revalidate	—	Must recheck with server after expiry
no-cache	—	Cache but always revalidate first
private	—	Only browser cache, not CDN/proxy

A+

Third-Party Impact

4% third-party, 0 ms blocking

PASS

4% third-party, 0 ms blocking

Third-party code accounts for 4% of page weight (131.6 KiB of 2.9 MiB)

Third-party blocking time is low (0 ms)

96%

First-party Third-party

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are compressed

All text resources are properly compressed.

A+

JS Execution Cost

330ms total JS execution

PASS

330ms total JS execution

https://cdn.jsdelivr.net/npm/chart.js@3.7.1: 93ms CPU time

https://rsf.org/cdn-cgi/scripts/7d0fa10a/cloudflar...: 84ms CPU time

https://rsf.org/en: 80ms CPU time

Unattributable: 73ms CPU time

Third-party scripts: 167ms (51% of total)

Main Thread Breakdown

Other 36% Script Evaluation 30% Style & Layout 20% Script Parsing & Compilation 4% Rendering 4% Parse HTML & CSS 4%

Script	Total	Scripting	Parse/Compile	Party
https://cdn.jsdelivr.net/npm/chart.js@3.7.1	93ms	23ms	4ms	3rd
https://rsf.org/cdn-cgi/scripts/7d0fa10a/cloudflare-static/rocket-loader.min.js	84ms	61ms	0ms	1st
https://rsf.org/en	80ms	3ms	0ms	1st
Unattributable	73ms	2ms	0ms	3rd

A+

Font Loading

5 fonts (92 KB)

PASS

5 fonts (92 KB)

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

Web fonts

5

92 KB total

Render-blocking

0

of 5

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

l woff2 swap

Size 17 KB

Load time 18 ms

Start 304 ms

Risk FOUT — text flashes from fallback to web font

l woff2 swap

Size 18 KB

Load time 21 ms

Start 304 ms

Risk FOUT — text flashes from fallback to web font

rsf_icon.ttf ttf swap

Size 8 KB

Load time 56 ms

Start 304 ms

Risk FOUT — text flashes from fallback to web font

Convert to woff2 for ~30% smaller file size

MediaSansSemiCondensed-... woff2 swap

Size 31 KB

Load time 54 ms

Start 305 ms

Risk FOUT — text flashes from fallback to web font

l woff2 swap

Size 18 KB

Load time 22 ms

Start 305 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 ~2 KB and ~4 ms

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+

Green Hosting

Whether the site is served from green-energy infrastructure

PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall

58 requests over 676ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

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

INFO

51% of JavaScript execution is third-party

First-party Third-party 167ms · 66KB · €2/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
jsDelivr cdn.jsdelivr.net	CDN	93ms	66 KB	64%	€1/mo	Optional
Unattributable Unattributable	Other	73ms	0 KB	—	€1/mo	Optional

jsDelivr

CDN

Optional

Execution 93ms

Transfer 66 KB

Unused 64%

Monthly Cost €1/mo

Unattributable

Other

Optional

Execution 73ms

Transfer 0 KB

Monthly Cost €1/mo

51% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

64% of jsDelivr's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

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

Send Feedback