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<canvas>

Use the HTML <canvas> element with the canvas scripting 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 non standard
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.
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

The displayed size of the canvas can be changed using a stylesheet. The image is scaled during rendering to fit the styled size. If your renderings seem distorted, try specifying your width and height attributes explicitly in the <canvas> attributes, and not using CSS.

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> 

If your canvas does not use transparency set the moz-opaque attribute on the canvas tag. This information can be used internally to optimize rendering. However, this attribute has not been standardized and only works in Mozilla-based rendering engines.

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

Specifications

Specification Status Comment
WHATWG 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

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1.0 (Yes) 1.5 (1.8)[1]
6.0 (6.0)[2]
12.0 (12.0)[3]
9.0 9.0[4] 2.0[5]
moz-opaque No support No support 3.5 (1.9.1) No support No support No support
Feature Firefox Mobile (Gecko) Android Edge IE Mobile Opera Mobile Safari Mobile
Basic support 1.5 (1.8)[1]
6.0 (6.0)[2]
12.0 (12.0)[3]
? (Yes) ? ? 1.0
moz-opaque 1.0 (1.9.1) No support No support No support No support No support

[1] Before Gecko 5.0 (Firefox 5.0 / Thunderbird 5.0 / SeaMonkey 2.2), the canvas width and height were signed integers instead of unsigned integers.

[2] Prior to Gecko 6.0 (Firefox 6.0 / Thunderbird 6.0 / SeaMonkey 2.3), a <canvas> element with a zero width or height would be rendered as if it had default dimensions.

[3] Before Gecko 12.0 (Firefox 12.0 / Thunderbird 12.0 / SeaMonkey 2.9), if JavaScript is disabled, the <canvas> element was being rendered instead of showing the fallback content as per the specification. Now the fallback content is rendered instead.

[4] See the changelog for Opera 9.0.

[5] 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. Those versions of Safari (prior to version 2.0) will render the content of the fallback in addition to the canvas itself unless you use CSS tricks to mask it. Fortunately, users of these versions of Safari are rare nowadays.

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/canvas