Performance: interactionCount property

The read-only performance.interactionCount property represents the number of real-user interactions that have occurred on the page since it was loaded.

Only discrete interactions with an interactionId — such as clicks and key events — are counted. Other interactions, such as scroll interactions, are excluded.

This is useful when calculating Interaction to Next Paint (INP), and in particular to exclude outliers for long-lived pages. INP takes the 98th percentile of interactions for a page and so excludes 1 in every 50 interactions as "outliers" that are not reflective of overall page responsiveness.

Value

A number, which is initially 0, and increments by 1 with each discrete interaction as measured by PerformanceEventTiming, where an PerformanceEventTiming.interactionId is assigned.

Examples

Checking the number of interactions to accurately calculate INP

For pages with a large number of interactions, you can recalculate INP after excluding 1 out of every 50 outliers using the following pattern:

js
if (performance.interactionCount >= 50) {
  recalculateINP(); // Actual calculation is complex and is not shown here
}

Specifications

Specification
Event Timing API
# dom-performance-interactioncount

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
interactionCount
Chrome – Full support
Chrome 144 (Release date: 2026-01-13)
footnote Full support
Edge – Full support
Edge 144 (Release date: 2026-01-21)
footnote Full support
Firefox – Full support
Firefox 144 (Release date: 2025-10-14)
footnote Full support
Opera – Full support
Opera 128 (Release date: 2026-02-26)
footnote Full support
Safari – Full support
Safari 26.2 (Release date: 2025-12-12)
footnote Full support
Chrome Android – Full support
Chrome Android 144 (Release date: 2026-01-13)
footnote Full support
Firefox for Android – Full support
Firefox for Android 144 (Release date: 2025-10-14)
footnote Full support
Opera Android – Full support
Opera Android 95 (Release date: 2026-02-11)
footnote Full support
Safari on iOS – Full support
Safari on iOS 26.2 (Release date: 2025-12-12)
footnote Full support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – Full support
WebView Android 144 (Release date: 2026-01-13)
footnote Full support
WebView on iOS – Full support
WebView on iOS 26.2 (Release date: 2025-12-12)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support

See also