HTML Audio/Video DOM loadstart Event

Alert that the video is starting to load:

let vid = document.getElementById("myVideo");
vid.onloadstart = function() {
alert("Starting to load video");
};

More "Try it Yourself" examples below.

Definition and Usage

The loadstart event occurs when the browser starts looking for the specified audio/video. This is when the loading process starts.

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
loadstart	Yes	9.0	Yes	Yes	Yes

In HTML:

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

In JavaScript:

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

In JavaScript, using the addEventListener() method:

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

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

Alert that the audio is starting to load:

let aud = document.getElementById("myAudio");
aud.onloadstart = function() {
alert("Starting to load video");
};