WCAG 1.2.2 Captions: A Guide to Accessible Video and Multimedia

WCAG 1.2.2 requires captions for prerecorded synchronized media. If your site hosts videos with spoken words or important sound cues, captions must be provided so people who are deaf or hard of hearing can follow the content.

What WCAG 1.2.2 actually requires

WCAG 1.2.2 is a success criterion for prerecorded time-based media. It says captions must be provided for all prerecorded audio content in synchronized media. Captions must convey the spoken words and relevant non-speech information needed to understand the content.

Key elements captions must include

• Spoken dialogue timed to the speech
• Speaker identification when not obvious from the visuals
• Non-speech information such as music mood, sound effects, or alarms when essential
• Accurate transcription of words and important noises

When 1.2.2 applies — and when it does not

It applies to prerecorded videos that have audio tracks synchronized with video. If a video contains spoken words, captions are required. If a video has no audio at all, captions are not required under 1.2.2, but consider a text alternative.

For audio-only content, a transcript is the appropriate alternative. Live captions are covered by separate WCAG criteria and have different requirements.

Captions versus subtitles versus transcripts

Use plain terms so the requirement is clear.

• Captions include speech and non-speech cues. They are for viewers who cannot hear the audio.
• Subtitles usually translate spoken language but often omit non-speech cues.
• Transcripts are text versions of the audio and can be useful as a supplement, not a replacement, for captions on synchronized media.

Common caption file formats

Choose a format your player supports. Common formats are WebVTT (.vtt), SubRip (.srt) and TTML/DFXP (.ttml). WebVTT is widely supported in modern browsers and HTML5 players.

Example WebVTT block (very short):

WEBVTT
00:00:00.000 –> 00:00:03.000
[Phone ringing] Hello, I’m calling about your order.

Practical step-by-step workflow

1. Create a verbatim transcript. Include speaker labels and non-speech sounds in square brackets or parentheses.
2. Timecode the transcript. Break text into short caption frames that match the audio.
3. Export a caption file in the format your player needs (VTT, SRT or TTML).
4. Upload and associate the file with the video asset. For hosted players use their caption upload option. For HTML5 video use <track kind=“captions”> with the VTT file.
5. Proofread in context while watching the video. Fix timing and readability issues.
6. Publish with user controls so viewers can switch captions on or off when closed captions are used.

Roles and rough times

• Transcriber: prepares verbatim text. For a 5-minute video expect 15 to 30 minutes depending on complexity.
• Captioner: timecodes and formats captions. Usually 1.5 to 3 times the video length.
• Reviewer: checks accuracy on the final player. Allow a short pass with the native player and a second pass on mobile.

Quality checklist for WCAG 1.2.2 captions

• All spoken words are present and accurate.
• Non-speech sounds that matter are described, for example, [door slams], [ominous music].
• Speakers are identified when needed.
• Timing matches the audio so captions appear when the words are spoken.
• Captions are readable on common devices and in fullscreen.

Common mistakes and how to fix them

• Relying solely on auto-captions. Automated captions help but often miss names, jargon and sounds. Always review and correct them.
• Captioning only speech. If a sound conveys essential meaning, add a short description.
• Poor timing or too much text. Break lines so viewers can read comfortably before text disappears.
• No speaker labels. Add labels on-screen when it is not clear who is speaking.

Testing methods

• Mute the video and read the captions. They must still explain the content.
• Switch captions on and off using keyboard controls. Ensure caption selection is reachable by keyboard.
• View captions on desktop and mobile, in portrait and landscape, and in fullscreen mode.
• Ask a person who is deaf or hard of hearing to review the captions for clarity and usefulness.

Practical policy and production tips

• Include captioning in project budgets. Plan roughly 1.5 to 3 times the video length for captioning work.
• Add a caption requirement to creative briefs and vendor contracts so it is not an afterthought.
• Decide whether to deliver closed captions (user toggle) or open captions (burned in). Closed captions give users control.

Where to go next

Use this guide as an operational checklist for WCAG 1.2.2 compliance. For technical details about file formats and player integration consult your platform documentation and captioning style guides used by broadcasters and accessibility teams.