How do I measure a page’s performance?

Scan the page

Scan the page from the home page. Performance is measured alongside the other checks and takes longer, so the rest of the report arrives first and the panel says “Performance scan in progress” until PageSpeed answers. It is measured once, with that scan: opening the report’s link later shows the numbers from that day.

Read the Performance panel

The panel sits after the checks. Its dial is the Lab score, from Lab test (simulated mobile): one run on a simulated mid-range phone over a slow connection. Beside it, Real users: Passing or Real users: Failing says what real Chrome visitors experienced over the last 28 days. A page without enough traffic for Google to report shows No real-user data yet, and the lab test is the guide.

Each measurement opens like a check, with what good looks like. Performance sits in Measured, not scored: it is shown, never counted.

If it could not be measured

The panel says why in one line, and the Performance card reads Couldn’t measure. Where another try can help, such as PageSpeed running out of time on a heavy page, it offers Rescan this page. Where it can’t, such as a site that turns away PageSpeed itself, it says so and offers no button. A performance check also counts toward the scan limit of 8 a minute, so a fast run of rescans can be asked to wait.

In a site scan, read Homepage performance

A site scan measures the homepage only. The site report, and the site’s page under Your sites, show it as Homepage performance, with its own dial; it doesn’t move the site score. Open the homepage report shows the full panel.

Measure another page of the site

Under Pages we scanned, press Open beside the page. Its Performance panel says Not recorded. Press Run a new single-page scan: it scans that page again, performance included, and adds the new scan to the page’s history. The report you opened stays exactly as it was, because a measurement taken today never gets attached to an older scan.

The same button appears on any older page report that has no measurement.