Opening the Lighthouse panel
Open Chrome DevTools
Press
F12 or Ctrl+Shift+I (Windows/Linux) / Cmd+Option+I (macOS), or right-click anywhere on the page and select Inspect.Navigate to the Lighthouse panel
Click the Lighthouse tab in the DevTools toolbar. If you don’t see it, click the
» overflow menu to find it.Configure categories and mode
Choose the audit categories you want to run (Performance, Accessibility, Best Practices, SEO) and select a mode (Navigation, Timespan, or Snapshot). Select a device form factor: Mobile or Desktop.
Audit modes
DevTools exposes all three Lighthouse modes directly in the panel.Throttling settings
By default, Lighthouse simulates a mid-tier mobile device on a slow 4G connection. You can adjust this in the Throttling section of the Lighthouse panel:- Simulated throttling (default) — Lighthouse collects data at full speed and then mathematically models what the experience would be on a throttled connection. Fast and reproducible.
- DevTools throttling — applies actual network and CPU throttling in the browser during the run. More realistic but can introduce variability.
- No throttling — runs without any throttling applied. Useful for debugging, but scores will not reflect real-world conditions.
Viewing and exporting reports
After a run, the report appears directly in the Lighthouse panel. From there you can:- Expand audits — click any audit to see details, affected elements, and guidance.
- Export as HTML or JSON — click the download icon (or the Export dropdown) at the top of the report to save the report to disk.
- Open in Lighthouse Viewer — click Export → Open in Lighthouse Viewer to open the report in the online viewer at https://googlechrome.github.io/lighthouse/viewer/. You can also drag a saved JSON report onto the viewer.
- Share via GitHub Gist — in the online viewer, click the share icon and sign in to GitHub. Reports are saved as secret Gists under your account.
The online viewer at https://googlechrome.github.io/lighthouse/viewer/ accepts JSON reports exported from any Lighthouse run — CLI, Node module, or DevTools.
Multi-step flows
DevTools supports single Navigation, Timespan, and Snapshot runs individually. It does not support combining multiple steps into a single multi-step user flow report.To run a multi-step user flow — for example, navigating to a page, interacting with it, and then snapshotting the result — use the Node API with Puppeteer.