Test site

Every load of this page reports a pageview and, once you leave or switch tabs, its Core Web Vitals. The controls below make the numbers move.

Interactions (INP)

A fast click, a click that blocks the main thread for 300 ms, and one for 800 ms.

Layout shift (CLS)

Inserts a banner above this card without reserving space for it.

Events and revenue

Custom event, a declarative event, and a revenue event in EUR.

Keyboard and checkout return

A focusable div that fires on Enter or Space, and a link that comes back like a Stripe checkout.

Tab here, press Enter
Return with ?session_id=cs_…

Visitor id the collector answered with: none yet

Navigation

An in-page route change (no new vitals) and an outbound link.

Outbound to tracing.tools

Scroll goal

Fires reached_bottom once, after half of this card has been on screen for 500 ms.

Then

Switch tabs or close the page. The vitals report is sent on visibilitychange.