RTCInboundRtpStreamStats: totalAssemblyTime property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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

The totalAssemblyTime property of the RTCInboundRtpStreamStats dictionary indicates the total time spent assembling successfully decoded video frames that were transported in multiple RTP packets.

Note: The value is undefined for audio streams.

Value

A number, in seconds.

Description

The property is updated whenever a video frame that was transported in multiple RTP packets is successfully decoded. The time increment is calculated by subtracting the timestamp of the last and first RTP packets that contained the video frame data. The time is not updated for video frames that are not decoded, or that are transported entirely within one RTP packet.

The average assembly time can be determined by dividing totalAssemblyTime by framesAssembledFromMultiplePackets. A higher average assembly time might indicate network issues or inefficiencies in the receiving pipeline.

Specifications

Specification
Identifiers for WebRTC's Statistics API
# dom-rtcinboundrtpstreamstats-totalassemblytime

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
totalAssemblyTime in 'inbound-rtp' stats
Experimental
Chrome – No support
Chrome
footnote No support
Edge – No support
Edge
footnote No support
Firefox – Full support
Firefox 142 (Release date: 2025-08-19)
footnote Full support
Opera – No support
Opera
footnote No support
Safari – No support
Safari
footnote No support
Chrome Android – No support
Chrome Android
footnote No support
Firefox for Android – Full support
Firefox for Android 142 (Release date: 2025-08-19)
footnote Full support
Opera Android – No support
Opera Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – No support
WebView Android
footnote No support
WebView on iOS – No support
WebView on iOS
footnote No support

Legend

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

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.