What do the HTML <track> kind values and TextTrack modes mean for description tracks, and is there evidence that browsers voice kind="descriptions" themselves?
The HTML Standard defines a 'descriptions' text track as text intended to be synthesised as audio when the picture can't be seen, and makes voicing it a browser (user agent) job: a showing descriptions track is made available non-visually. Evidence that browsers actually voice such tracks is thin, so web players implement it themselves.
The HTML Standard defines a 'descriptions' text track as text intended to be synthesised as audio when the picture can't be seen, and makes voicing it a browser (user agent) job: a showing descriptions track is made available non-visually. Evidence that browsers actually voice such tracks is thin, so web players implement it themselves.
Curator qualifications: Specs, docs and code read 2026-10-22; no browser or player tested. MDN compat data and Able Player issue 301 (2018) carried from producer reading.
Limitations: Specs, docs and code read 2026-10-22; no browser or player tested.
Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
"citations": [
{
"url": "https://html.spec.whatwg.org/multipage/media.html",
"note": "HTML Standard multipage media.html (Last Updated 20 October 2026), track kind table and showing mode"
},
{
"url": "https://github.com/ableplayer/ableplayer/blob/8d235f977689f310a074b3ddcf68e8d19a7ed4ae/README.md",
"note": "HTML Standard multipage media.html (Last Updated 20 October 2026), track kind table and showing mode"
},
{
"url": "https://github.com/ableplayer/ableplayer/issues/301",
"note": "HTML Standard multipage media.html (Last Updated 20 October 2026), track kind table and showing mode"
},
{
"url": "https://github.com/mdn/browser-compat-data/blob/d8fae3e315612cc015430e40310f827edbf25a0d/html/elements/track.json",
"note": "HTML Standard multipage media.html (Last Updated 20 October 2026), track kind table and showing mode"
}
]
}Evidence claims
- [sourced_fact] The HTML Standard defines a 'descriptions' text track as text intended to be synthesised as audio when the picture can't be seen, and makes voicing it a browser (user agent) job: a showing descriptions track is made available non-visually. Evidence that browsers actually voice such tracks is thin, so web players implement it themselves. · locator: HTML Standard multipage media.html (Last Updated 20 October 2026), track kind table and showing mode source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |
Linked records
- cites → https://github.com/ableplayer/ableplayer/blob/8d235f977689f310a074b3ddcf68e8d19a7ed4ae/README.md
- cites → https://github.com/ableplayer/ableplayer/issues/301
- cites → https://github.com/mdn/browser-compat-data/blob/d8fae3e315612cc015430e40310f827edbf25a0d/html/elements/track.json
- cites → https://html.spec.whatwg.org/multipage/media.html