The HTMLTrackElement interface represents an HTML <track> element within the [[../../../Glossary/DOM|DOM]]. This element can be used as a child of either <audio> or <video> to specify a text track containing information such as closed captions or subtitles.
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a:hover text { fill: #0095DD; pointer-events: all;}
Properties
Inherits properties from its parent, HTMLElement.
HTMLTrackElement.kind- Is a
DOMStringthat reflects thekindHTML attribute, indicating how the text track is meant to be used. Possible values are:subtitles,captions,descriptions,chapters, ormetadata. HTMLTrackElement.src- Is a
DOMStringthat reflects thesrcHTML attribute, indicating the address of the text track data. HTMLTrackElement.srclang- Is a
DOMStringthat reflects thesrclangHTML attribute, indicating the language of the text track data. HTMLTrackElement.label- Is a
DOMStringthat reflects thelabelHTML attribute, indicating a user-readable title for the track. HTMLTrackElement.default- A
Booleanreflecting thedefaultattribute, indicating that the track is to be enabled if the user's preferences do not indicate that another track would be more appropriate. HTMLTrackElement.readyStateRead only- Returns an
unsigned shortthat show the readiness state of the track:Constant Value Description NONE0 Indicates that the text track's cues have not been obtained. LOADING1 Indicates that the text track is loading and there have been no fatal errors encountered so far. Further cues might still be added to the track by the parser. LOADED2 Indicates that the text track has been loaded with no fatal errors. ERROR3 Indicates that the text track was enabled, but when the user agent attempted to obtain it, this failed in some way. Some or all of the cues are likely missing and will not be obtained. HTMLTrackElement.trackRead only- Returns
TextTrackis the track element's text track data.
Methods
No specific method; inherits methods from its parent, HTMLElement.
Events
The following events may be fired on a <track> element, in addition to any that may be fired at its parent, HTMLElement.
cuechange- Sent when the underlying
TextTrackhas changed the currently-presented cues. This event is always sent to theTextTrackbut is also sent to theHTMLTrackElementif one is associated with the track. You may also use theoncuechangeevent handler to establish a handler for this event.
Usage notes
Loading of the track's text resource
The WebVTT or TTML data describing the actual cues for the text track isn't loaded if the track's mode is initially in the disabled state. If you need to be able to perform any processing on the track after the <track> is set up, you should instead ensure that the track's mode is either hidden (if you don't want it to start out being presented to the user) or showing (to initially display the track). You can then change the mode as desired later.
Specifications
| Specification | Status | Comment |
| HTML Living StandardThe definition of 'HTMLTrackElement' in that specification. | Living Standard | |
| HTML5The definition of 'HTMLTrackElement' in that specification. | Recommendation | Initial definition. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
HTMLTrackElement
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 Notes' Prior to Firefox 50, text tracks would only load if the <track> element is in a document. No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 Notes' Prior to Firefox 50, text tracks would only load if the <track> element is in a document. No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
cuechange event
|
Chrome
Full support Yes |
Edge
Full support ≤79 |
Firefox
Full support 68 |
IE
No support No |
Opera
? |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support 68 |
Opera Android
? |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
default
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
kind
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
label
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
readyState
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
src
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 Notes' Setting the Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 Notes' Setting the Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
srclang
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
track
|
Chrome
Full support 23 |
Edge
Full support 12 |
Firefox Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12 |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support 25 |
Firefox Android Full support 31 Full support 31 No support 24 — 30 Disabled' From version 24 until version 30 (exclusive): this feature is behind the |
Opera Android
Full support 12 |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support 1.5 |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- See implementation notes.'
- See implementation notes.
- User must explicitly enable this feature.'
- User must explicitly enable this feature.
See also
- The HTML element implementing this interface:
<track>.
HTMLTrackElement by Mozilla Contributors is licensed under CC-BY-SA 2.5.