Use the HTML <canvas> element with either the canvas scripting API or the WebGL API to draw graphics and animations.

Content categories Flow content, phrasing content, embedded content, palpable content.
Permitted content Transparent but with no interactive content descendants except for <a> elements, <button> elements, <input> elements whose type attribute is checkbox, radio, or button.
Tag omission None, both the starting and ending tag are mandatory.
Permitted parents Any element that accepts phrasing content.
Permitted ARIA roles Any
DOM interface HTMLCanvasElement

Attributes

This element's attributes include the global attributes.

height
The height of the coordinate space in CSS pixels. Defaults to 150.
moz-opaque
Lets the canvas know whether or not translucency will be a factor. If the canvas knows there's no translucency, painting performance can be optimized. This is only supported by Mozilla-based browsers; use the standardized canvas.getContext('2d', { alpha: false }) instead.
width
The width of the coordinate space in CSS pixels. Defaults to 300.

Usage notes

Alternative content

You may (and should) provide alternate content inside the <canvas> block. That content will be rendered both on older browsers that don't support canvas and in browsers with JavaScript disabled.

Required </canvas> tag

Unlike the <img> element, the <canvas> element requires the closing tag (</canvas>).

Sizing the canvas using CSS versus HTML

The displayed size of the canvas can be changed using CSS, but if you do this the image is scaled during rendering to fit the styled size, which can make the final graphics rendering end up being distorted.

It is better to specify your canvas dimensions by setting the width and height attributes directly on the <canvas> elements, either directly in the HTML or by using JavaScript.

Maximum canvas size

The maximum size of a <canvas> element is very large, but the exact size depends on the browser. The following is some data we've collected from various tests and other sources (e.g. Stack Overflow):

Browser Maximum height Maximum width Maximum area
Chrome 32,767 pixels 32,767 pixels 268,435,456 pixels (i.e., 16,384 x 16,384)
Firefox 32,767 pixels 32,767 pixels 472,907,776 pixels (i.e., 22,528 x 20,992)
Safari 32,767 pixels 32,767 pixels 268,435,456 pixels (i.e., 16,384 x 16,384)
IE 8,192 pixels 8,192 pixels ?

Note: Exceeding the maximum dimensions or area renders the canvas unusable — drawing commands will not work.

Examples

This code snippet adds a canvas element to your HTML document. A fallback text is provided if a browser is unable to render the canvas, or if can't read a canvas. Providing a useful fallback text or sub DOM helps to make the the canvas more accessible.

<canvas id="canvas" width="300" height="300">
  An alternative text describing what your canvas displays. 
</canvas> 

Then in the JavaScript code, call HTMLCanvasElement.getContext() to get a drawing context and start drawing onto the canvas:

<script>
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
ctx.fillStyle = 'green';
ctx.fillRect(10, 10, 100, 100);
</script>

Opaque canvas

If your canvas does not use transparency, you can tell the browser that your canvas is opaque, this will be used internally to optimize rendering. To do this, set alpha to false when getting the drawing context:

<script>
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d', { alpha: false });
</script>

Before the alpha option was standardized, you could use the moz-opaque attribute on the canvas tag. However, this only works in Mozilla-based rendering engines and should be avoided; check bug 878155 to track when this attribute will be removed.

<canvas id="myCanvas" moz-opaque></canvas>

Accessibility concerns

Alternative content

The <canvas> element on its own is just a bitmap and does not provide information about any drawn objects. Canvas content is not exposed to accessibility tools as semantic HTML is. In general, you should avoid using canvas in an accessible website or app. The following guides can help to make it more accessible.

Specifications

Specification Status Comment
HTML Living Standard
The definition of '<canvas>' in that specification.
Living Standard  
HTML5
The definition of '<canvas>' in that specification.
Recommendation Initial definition

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
canvasChrome Full support 1Edge Full support YesFirefox Full support 1.5
Notes
Full support 1.5
Notes
Notes Before Firefox 5, the canvas width and height were signed integers instead of unsigned integers.
Notes Prior to Firefox 6, a <canvas> element with a zero width or height would be rendered as if it had default dimensions.
Notes Before Firefox 12, if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Since then, the fallback content is rendered instead.
IE Full support 9Opera Full support 9Safari Full support 2
Notes
Full support 2
Notes
Notes Although early versions of Apple's Safari browser don't require the closing tag, the specification indicates that it is required, so you should be sure to include it for broadest compatibility. Versions of Safari prior to version 2 will render the content of the fallback in addition to the canvas itself unless you use CSS tricks to mask it.
WebView Android Full support 37Chrome Android Full support 18Firefox Android Full support 4
Notes
Full support 4
Notes
Notes Before Firefox 5, the canvas width and height were signed integers instead of unsigned integers.
Notes Prior to Firefox 6, a <canvas> element with a zero width or height would be rendered as if it had default dimensions.
Notes Before Firefox 12, if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Since then, the fallback content is rendered instead.
Opera Android No support NoSafari iOS Full support 1Samsung Internet Android Full support Yes
heightChrome Full support 1Edge Full support YesFirefox Full support 1.5
Notes
Full support 1.5
Notes
Notes Before Firefox 5, the canvas width and height were signed integers instead of unsigned integers.
Notes Prior to Firefox 6, a <canvas> element with a zero width or height would be rendered as if it had default dimensions.
Notes Before Firefox 12, if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Since then, the fallback content is rendered instead.
IE Full support 9Opera Full support 9Safari Full support 2
Notes
Full support 2
Notes
Notes Although early versions of Apple's Safari browser don't require the closing tag, the specification indicates that it is required, so you should be sure to include it for broadest compatibility. Versions of Safari prior to version 2 will render the content of the fallback in addition to the canvas itself unless you use CSS tricks to mask it.
WebView Android Full support 37Chrome Android Full support 18Firefox Android Full support 4
Notes
Full support 4
Notes
Notes Before Firefox 5, the canvas width and height were signed integers instead of unsigned integers.
Notes Prior to Firefox 6, a <canvas> element with a zero width or height would be rendered as if it had default dimensions.
Notes Before Firefox 12, if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Since then, the fallback content is rendered instead.
Opera Android No support NoSafari iOS Full support 1Samsung Internet Android Full support Yes
moz-opaque
Non-standard
Chrome No support NoEdge No support NoFirefox Full support 3.5IE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoFirefox Android Full support 4Opera Android No support NoSafari iOS No support NoSamsung Internet Android No support No
widthChrome Full support 1Edge Full support YesFirefox Full support 1.5
Notes
Full support 1.5
Notes
Notes Before Firefox 5, the canvas width and height were signed integers instead of unsigned integers.
Notes Prior to Firefox 6, a <canvas> element with a zero width or height would be rendered as if it had default dimensions.
Notes Before Firefox 12, if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Since then, the fallback content is rendered instead.
IE Full support 9Opera Full support 9Safari Full support 2
Notes
Full support 2
Notes
Notes Although early versions of Apple's Safari browser don't require the closing tag, the specification indicates that it is required, so you should be sure to include it for broadest compatibility. Versions of Safari prior to version 2 will render the content of the fallback in addition to the canvas itself unless you use CSS tricks to mask it.
WebView Android Full support 37Chrome Android Full support 18Firefox Android Full support 4
Notes
Full support 4
Notes
Notes Before Firefox 5, the canvas width and height were signed integers instead of unsigned integers.
Notes Prior to Firefox 6, a <canvas> element with a zero width or height would be rendered as if it had default dimensions.
Notes Before Firefox 12, if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Since then, the fallback content is rendered instead.
Opera Android No support NoSafari iOS Full support 1Samsung Internet Android Full support Yes

Legend

Full support  
Full support
No support  
No support
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.
See implementation notes.
See implementation notes.

See also