HTML Audio/Video DOM durationchange Event

Alert that the duration of the video has changed:

let vid = document.getElementById("myVideo");
vid.ondurationchange = function() {
alert("The video duration has changed");
};

More "Try it Yourself" examples below.

Definition and Usage

The durationchange event occurs when the duration data of the specified audio/video is changed.

Note: When an audio/video is loaded, the duration will change from "NaN" to the actual duration of the audio/video.

During the loading process of an audio/video, the following events occur, in this order:

The numbers in the table specify the first browser version that fully supports the event.

Event
durationchange	Yes	9.0	Yes	Yes	Yes

In HTML:

<audio|video ondurationchange="myScript">Try it

In JavaScript:

audio|video.ondurationchange=function(){myScript};Try it

In JavaScript, using the addEventListener() method:

audio|video.addEventListener("durationchange", myScript);Try it

Supported HTML tags:	<audio> and <video>
Supported JavaScript objects:	Audio, Video

Alert that the duration of the audio has changed:

let aud = document.getElementById("myAudio");
aud.ondurationchange = function() {
alert("The audio duration has changed");
};