Captions make video elements usable for deaf or hearing-impaired users,
providing critical information such as who is talking, what they're saying,
and other non-speech information.
Lighthouse reports any
<video> elements that are missing a
with the attribute
How to fix the problem
To fix the problem,
add at least one track element to the
<video width="300" height="200">
<source src="marathonFinishLine.mp4" type="video/mp4">
<track src="captions_en.vtt" kind="captions" srclang="en" label="english_captions">
<track src="audio_desc_en.vtt" kind="descriptions" srclang="en" label="english_description">
<track src="captions_es.vtt" kind="captions" srclang="es" label="spanish_captions">
<track src="audio_desc_es.vtt" kind="descriptions" srclang="es" label="spanish_description">
Learn more in
<video> elements must have a
<track> for captions.
The example above includes both captions for hearing impaired users,
and audio descriptions for visually impaired users.
Audio descriptions provide context beyond dialog, such as scenery, facial expressions.
See also Ensures
<video> elements have audio descriptions.
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