How to Run Lighthouse Audits in Chrome DevTools

· Category: VS Code & Developer Tools

Short answer

Lighthouse is an open-source auditing tool built into Chrome DevTools. It generates scores and recommendations for performance, accessibility, best practices, SEO, and Progressive Web Apps.

Steps

  1. Open DevTools and click the Lighthouse tab (or use the arrows menu).
  2. Select the categories to audit: Performance, Accessibility, Best Practices, SEO, or PWA.
  3. Choose a device mode: Mobile or Desktop.
  4. Click "Analyze page load" and wait for the audit to complete.
  5. Review the scores and detailed improvement suggestions.

Tips

  • Run audits in Incognito mode to prevent extensions from skewing results.
  • Focus on the metrics with the largest impact, such as LCP and CLS.
  • Export reports as JSON for continuous integration pipelines.

Common issues

  • Scores may vary between runs due to network and CPU conditions.
  • Third-party scripts often dominate the performance diagnosis.