The <source> specifies multiple media resources for the <picture>, the <audio> element, or the <video> element. It is an empty element. It is commonly used to serve the same media content in multiple formats supported by different browsers.

Content categories None.
Permitted content None, it is an empty element.
Tag omission It must have start tag, but must not have an end tag.
Permitted parents A media element—<audio> or <video>—and it must be placed before any flow content or <track> element. A <picture> element, and it must be placed before the <img> element.
Permitted ARIA roles None
DOM interface HTMLSourceElement


This element includes the global attributes.

Is a list of source sizes that describes the final rendered width of the image represented by the source. Each source size consists of a comma-separated list of media condition-length pairs. This information is used by the browser to determine, before laying the page out, which image defined in srcset to use.
The sizes attribute has an effect only when the <source> element is the direct child of a <picture> element.
Required for <audio> and <video>, address of the media resource. The value of this attribute is ignored when the <source> element is placed inside a <picture> element.
A list of one or more strings separated by commas indicating a set of possible images represented by the source for the browser to use. Each string is composed of:
  1. one URL to an image,
  2. a width descriptor, that is a positive integer directly followed by 'w'. The default value, if missing, is the infinity.
  3. a pixel density descriptor, that is a positive floating number directly followed by 'x'. The default value, if missing, is 1x.

Each string in the list must have at least a width descriptor or a pixel density descriptor to be valid. Among the list, there must be only one string containing the same tuple of width descriptor and pixel density descriptor.
The browser chooses the most adequate image to display at a given point of time.
The srcset attribute has an effect only when the <source> element is the direct child of a <picture> element.

The MIME-type of the resource, optionally with a codecs parameter. See RFC 4281 for information about how to specify codecs.
Media query of the resource's intended media; this should be used only in a <picture> element.

If the type attribute isn't specified, the media's type is retrieved from the server and checked to see if the user agent can handle it; if it can't be rendered, the next <source> is checked. If the type attribute is specified, it's compared against the types the user agent can present, and if it's not recognized, the server doesn't even get queried; instead, the next <source> element is checked at once.


This example demonstrates how to offer a video in Ogg format for users whose browsers support Ogg format, and a QuickTime format video for users whose browsers support that. If the audio or video element is not supported by the browser, a notice is displayed instead. If the browser supports the element but does not support any of the specified formats, an error event is raised and the default media controls (if enabled) will indicate an error. See also the list of media formats supported by the audio and video elements in various browsers.

<video controls>
  <source src="foo.webm" type="video/webm">
  <source src="foo.ogg" type="video/ogg"> 
  <source src="foo.mov" type="video/quicktime">
  I'm sorry; your browser doesn't support HTML5 video.

For more examples, see Using audio and video in Firefox.


Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes Yes 3.51 9 Yes Yes
media Yes Yes 15 9 Yes Yes
sizes Yes Yes



? ? ?
src Yes Yes 3.5 9 Yes Yes
srcset Yes Yes



? ? ?
type Yes Yes 3.5 9 Yes Yes
Feature Android webview Chrome for Android Edge mobile Firefox for Android IE mobile Opera Android iOS Safari
Basic support Yes Yes Yes 41 ? ? ?
media Yes Yes Yes 15 ? ? ?
sizes Yes Yes Yes



? ? ?
src Yes Yes Yes 4 ? ? ?
srcset Yes Yes Yes



? ? ?
type Yes Yes Yes 4 ? ? ?

1. Until Firefox 15, Firefox picked the first source element that has a type matching the MIME-type of a supported media format; see bug 449363 for details.

2. From version 33: this feature is behind the dom.image.picture.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

See also

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