This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The NetworkInformation.rtt read-only property returns the estimated effective round-trip time of the current connection, rounded to the nearest multiple of 25 milliseconds. This value is based on recently observed application-layer RTT measurements across recently active connections. It excludes connections made to a private address space. If no recent measurement data is available, the value is based on the properties of the underlying connection technology.

Note: This feature is available in Web Workers.


rtt = NetworkInformation.rtt

Return value

A number.


Specification Status Comment
Network Information API
The definition of 'rtt' in that specification.
Editor's Draft Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 61 No support No support 48 No support
Available in workers 61 No support No support 48 No support
Feature Android Webview Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 50 38 31.0 (31) No support 37 No support
Available in workers 50 38 53.0 (53) No support 37 No support

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