Start a Lighthouse Audit in Chrome
Lighthouse 12 in Chrome 131 checks website accessibility step by step.
- web
- tools
- barrierefreiheit
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AI-assisted · editorially reviewed Details
Update Chrome
Launch Chrome version 131. Check for updates in settings. Without the current release the audit misses new contrast rules introduced in 2025.
Open DevTools
Press F12 or Ctrl+Shift+I. The Lighthouse tab appears only from this build onward. Skip the step and you run the audit via command line — graphical previews are lost.
Select category
Enable only “Accessibility”. Other categories like Performance extend runtime without benefit for this task. The tool then scans ARIA attributes and color contrasts specifically.
Set device and mode
Choose “Desktop” or “Mobile”. “Mobile” simulates 360-pixel width. Without a clear choice the report mixes values that are hard to assign later.
Generate report
Click “Analyze page load”. The process takes 30 to 90 seconds. Pages above 5 MB often cause the run to abort.
Read results
The score appears as a number from 0 to 100. Each red item lists the exact source line. Ignore warnings without line references — they cannot be quantified reliably.
Fix issues
Open the affected page in your editor. Raise contrast to at least 4.5:1. Repeat the audit right after each change. Otherwise the score stays the same.
Audit that often fails
Mobile simulation and real devices return different contrast values due to OS scaling. Always verify on an actual smartphone afterward.