The HTML <source> element 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

Attributes

This element includes the global attributes.

sizes
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.
src
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.
srcset
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.

type
The MIME-type of the resource, optionally with a codecs parameter. See RFC 4281 for information about how to specify codecs.
media
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.

Examples

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.
</video>

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

Specifications

Specification Status Comment
HTML Living Standard
The definition of '<source>' in that specification.
Living Standard  

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support YesEdge Full support YesFirefox Full support 3.5
Notes
Full support 3.5
Notes
Notes 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.
IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4
Notes
Full support 4
Notes
Notes 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.
Opera Android ? Safari iOS Full support YesSamsung Internet Android Full support Yes
media
Experimental
Chrome Full support YesEdge Full support YesFirefox Full support 15IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 15Opera Android ? Safari iOS Full support YesSamsung Internet Android Full support Yes
sizes
Experimental
Chrome Full support YesEdge Full support YesFirefox Full support 38
Full support 38
Full support 33
Disabled
Disabled 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.
IE ? Opera ? Safari Full support 9
Full support 9
Partial support 7
WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 38
Full support 38
Full support 33
Disabled
Disabled 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.
Opera Android ? Safari iOS Full support 9.2
Full support 9.2
Partial support 8
Samsung Internet Android Full support Yes
srcChrome Full support YesEdge Full support YesFirefox Full support 3.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4Opera Android ? Safari iOS Full support YesSamsung Internet Android Full support Yes
srcset
Experimental
Chrome Full support YesEdge Full support YesFirefox Full support 38
Full support 38
Full support 33
Disabled
Disabled 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.
IE ? Opera ? Safari Full support 9
Full support 9
Partial support 7
WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 38
Full support 38
Full support 33
Disabled
Disabled 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.
Opera Android ? Safari iOS Full support 9.2
Full support 9.2
Partial support 8
Samsung Internet Android Full support Yes
typeChrome Full support YesEdge Full support YesFirefox Full support 3.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4Opera Android ? Safari iOS Full support YesSamsung Internet Android Full support Yes

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.

See also