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Web vitals

Reignat can collect real-user performance signals from the same tracking script.

What is collected

The tracker captures Core Web Vitals and related browser performance timings when the browser supports them.

CLS

number

Cumulative Layout Shift, rounded to three decimal places.

FCP

milliseconds

First Contentful Paint.

LCP

milliseconds

Largest Contentful Paint.

TTFB

milliseconds

Time to First Byte from the navigation timing entry.

INP

milliseconds

Interaction to Next Paint approximation from event timing samples.

How it sends

Web vitals are sent as vitals events after the page has had time to settle, and again on page hide when needed.

Some metrics may be null if the browser does not expose the required performance API or the page closes before a metric is available.

Where to use it

Use the Performance view to find slow pages, compare browser or OS segments, and spot countries where real-user experience is worse than expected.