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https://ccc.de

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
91
GRADE
A
FIX
2
REVIEW
2
PASS
11
INFO
2

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

Mobile Desktop
87
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
92
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
81
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

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

2.82 s

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

3.30 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.

0.000

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

3.35 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.

3.31 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
17
11 PASS 2 REVIEW 2 FIX
D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (190.3 KiB of 190.5 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

C
Image Optimization
Action
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Warning::
https://www.ccc.de/images/header.png?1736906356 is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.ccc.de/images/chaosradio.png?173687506... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.ccc.de/images/ds.png?1736875191 is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.ccc.de/images/events.png?1736875302 is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
7 images 64 KB
0 oversized -0 KB
7 legacy format
4 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
190 KB transferred, 19 requests
PASS
190 KB transferred, 19 requests
Info::
Page weighs 186 KB (190 KB transferred)
Info::
19 HTTP requests
Info::
Estimated 0.04 g CO2 per page load
190 KB / 2.4 MB budget
190 KB transferred
19 requests
0.04 g CO2 per page load
JavaScript 95.0 KiB 50%
Images 63.9 KiB 34%
HTML 14.8 KiB 8%
CSS 13.0 KiB 7%
Other 3.7 KiB 2%
0 2.4 MB 4.9 MB
Under budget
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
JS Execution Cost
279ms total JS execution
PASS
279ms total JS execution
Info::
Unattributable: 148ms CPU time
Info::
https://www.ccc.de/javascripts/jquery-1.3.2.min.js...: 131ms CPU time
Warning::
Third-party scripts: 279ms (100% of total)

Main Thread Breakdown

Other 44% Style & Layout 26% Script Evaluation 19% Parse HTML & CSS 4% Script Parsing & Compilation 4% Rendering 3%
ScriptTotalScriptingParse/CompileParty
Unattributable148ms7ms0ms3rd
https://www.ccc.de/javascripts/jquery-1.3.2.min.js?1246657683131ms30ms7ms3rd
A+
Font Loading
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
A+
JS Bundles
7 scripts, 38 KB unused
PASS
7 scripts, 38 KB unused
Warning::
https://www.ccc.de/javascripts/jquery-1.3.2.min.js...: 38 KB unused (67%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 38 KB
38 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.ccc.de/javascripts/jquery-1.3.2.min.js?124665768356 KB38 KB (67%)✓3rd
https://www.ccc.de/javascripts/shadowbox/shadowbox.js?125319003521 KB—✓3rd
https://www.ccc.de/javascripts/public.js?17396744351 KB—✓3rd
https://www.ccc.de/javascripts/shadowbox/libraries/sizzle/sizzle.js13 KB—✓3rd
https://www.ccc.de/javascripts/shadowbox/languages/shadowbox-en.js1 KB—✓3rd
https://www.ccc.de/javascripts/shadowbox/players/shadowbox-img.js2 KB—✓3rd
https://www.ccc.de/javascripts/shadowbox/adapters/shadowbox-jquery.js1 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

A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A
Page Weight Inventory
19 resources · 190 KB · 38 KB savings available
PASS
19 resources · 190 KB · 38 KB savings available
Info::
Within 1MB page-weight target
Got: 190 KB
Warning::
18 third-party resources (100% of weight)
19 resources · 190.5 KiB · 18 third-party Within 1MB page-weight target
JavaScript 50% · 95.0 KiB
Image 35% · 67.5 KiB
Document 8% · 15.0 KiB
CSS 7% · 13.0 KiB

~37.6 KiB of savings available

Remove unused JavaScript: 37.6 KiB
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
19 requests over 605ms
INFO
0 ms 1.0 s 2.0 s 3.0 s FCP 2.8 s LCP 3.3 shttps://ccc.de// https://ccc.de/ — 302 — 194 B — 110 ms — http/1.1https://www.ccc.de/www.ccc.de/ https://www.ccc.de/ — 200 — 14.8 KiB — 180 ms — http/1.1https://www.ccc.de/stylesheets/ccc.css?1743181483www.ccc.de/stylesheets/ccc.css?1743... https://www.ccc.de/stylesheets/ccc.css?1743181483 — 200 — 10.8 KiB — 37 ms — http/1.1https://www.ccc.de/javascripts/jquery-1.3.2.min.js?1246657683www.ccc.de/javascripts/jquery-1.3.2... https://www.ccc.de/javascripts/jquery-1.3.2.min.js?1246657683 — 200 — 56.1 KiB — 170 ms — http/1.1https://www.ccc.de/javascripts/shadowbox/shadowbox.js?1253190035www.ccc.de/javascripts/shadowbox/sh... https://www.ccc.de/javascripts/shadowbox/shadowbox.js?1253190035 — 200 — 20.7 KiB — 136 ms — http/1.1https://www.ccc.de/stylesheets/shadowbox.css?1253190035www.ccc.de/stylesheets/shadowbox.cs... https://www.ccc.de/stylesheets/shadowbox.css?1253190035 — 200 — 2.2 KiB — 73 ms — http/1.1https://www.ccc.de/javascripts/public.js?1739674435www.ccc.de/javascripts/public.js?17... https://www.ccc.de/javascripts/public.js?1739674435 — 200 — 1.3 KiB — 106 ms — http/1.1https://www.ccc.de/images/header.png?1736906356www.ccc.de/images/header.png?173690... https://www.ccc.de/images/header.png?1736906356 — 200 — 14.2 KiB — 106 ms — http/1.1https://www.ccc.de/images/chaosradio.png?1736875067www.ccc.de/images/chaosradio.png?17... https://www.ccc.de/images/chaosradio.png?1736875067 — 200 — 13.0 KiB — 72 ms — http/1.1https://www.ccc.de/images/ds.png?1736875191www.ccc.de/images/ds.png?1736875191 https://www.ccc.de/images/ds.png?1736875191 — 200 — 2.5 KiB — 36 ms — http/1.1https://www.ccc.de/images/events.png?1736875302www.ccc.de/images/events.png?173687... https://www.ccc.de/images/events.png?1736875302 — 200 — 7.4 KiB — 36 ms — http/1.1https://www.ccc.de/images/media-ccc-de-banner.svg?1549308118www.ccc.de/images/media-ccc-de-bann... https://www.ccc.de/images/media-ccc-de-banner.svg?1549308118 — 200 — 6.4 KiB — 37 ms — http/1.1https://www.ccc.de/images/Fediverse.svg?1668911106www.ccc.de/images/Fediverse.svg?166... https://www.ccc.de/images/Fediverse.svg?1668911106 — 200 — 19.5 KiB — 35 ms — http/1.1https://www.ccc.de/javascripts/shadowbox/libraries/sizzle/sizzle.jswww.ccc.de/javascripts/shadowbox/li... https://www.ccc.de/javascripts/shadowbox/libraries/sizzle/sizzle.js — 200 — 12.5 KiB — 40 ms — http/1.1https://www.ccc.de/javascripts/shadowbox/languages/shadowbox-en.jswww.ccc.de/javascripts/shadowbox/la... https://www.ccc.de/javascripts/shadowbox/languages/shadowbox-en.js — 200 — 825 B — 39 ms — http/1.1https://www.ccc.de/javascripts/shadowbox/players/shadowbox-img.jswww.ccc.de/javascripts/shadowbox/pl... https://www.ccc.de/javascripts/shadowbox/players/shadowbox-img.js — 200 — 2.4 KiB — 39 ms — http/1.1https://www.ccc.de/javascripts/shadowbox/adapters/shadowbox-jquery.jswww.ccc.de/javascripts/shadowbox/ad... https://www.ccc.de/javascripts/shadowbox/adapters/shadowbox-jquery.js — 200 — 1.2 KiB — 38 ms — http/1.1https://www.ccc.de/images/Bluesky_Logo.svg?1737509920www.ccc.de/images/Bluesky_Logo.svg?... https://www.ccc.de/images/Bluesky_Logo.svg?1737509920 — 200 — 959 B — 37 ms — http/1.1https://www.ccc.de/favicon.icowww.ccc.de/favicon.ico https://www.ccc.de/favicon.ico — 200 — 3.5 KiB — 36 ms — http/1.1
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100% of JavaScript execution is third-party
First-party Third-party 279ms · 56KB · €3/mo
Unattributable
Other
Optional
Execution 148ms
Transfer 0 KB
Monthly Cost €2/mo
www.ccc.de
Other
Optional
Execution 131ms
Transfer 56 KB
Unused 67%
Monthly Cost €1/mo

100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

67% of www.ccc.de'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.

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