Page audit

A page audit loads a page in a browser and scores its performance, accessibility and best practices, listing the audits that cost it points. It needs a running copy of the app, usually a preview.

Finding it

Look for the audit's config in the repository (lighthouserc.json or .lighthouserc.* for Lighthouse CI) and in CI for the job that runs it. The config lists the pages, the number of runs and the assertions; the job names the address it audits.

Using it

• Several runs, the median: scores vary from run to run, so take the median of several (numberOfRuns in Lighthouse CI).
• Assertions per page: a minimum score per category or a limit per metric, so the job fails on what got worse.
• The same conditions every time: a preview on the same kind of machine, with the same throttling and nothing else heavy running.
• One page while working: npx lighthouse <url> --output=json audits a single page; lhci autorun runs the whole config as CI does.

Examples: Lighthouse, Lighthouse CI.