The HTMLCanvasElement.width property is a positive integer reflecting the width HTML attribute of the <canvas> element interpreted in CSS pixels. When the attribute is not specified, or if it is set to an invalid value, like a negative, the default value of 300 is used.

This is one of the two properties, the other being HTMLCanvasElement.height, that controls the size of the canvas.


var pxl = canvas.width;
canvas.width = pxl;


Given this <canvas> element:

<canvas id="canvas" width="300" height="300"></canvas>

You can get the width of the canvas with the following code:

var canvas = document.getElementById("canvas");
console.log(canvas.width); // 300


Specification Status Comment
WHATWG HTML Living Standard
The definition of 'HTMLCanvasElement.width' in that specification.
Living Standard No change since the latest snapshot, HTML5
The definition of 'HTMLCanvasElement.width' in that specification.
Working Draft  
The definition of 'HTMLCanvasElement.width' in that specification.
Recommendation Snapshot of the WHATWG HTML Living Standard containing the initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 4 3.6 (1.9.2) 9 9 3.1
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) 1.0 (1.9.2) (Yes) (Yes) (Yes)

See also


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