All video content has captions (open or closed) synchronized to audio

Captions are the primary mechanism through which deaf and hard-of-hearing users access spoken video content. WCAG 2.2 SC 1.2.2 (Level A) requires captions for all prerecorded synchronized media; SC 1.2.4 (Level AA) extends this to live video. Section 508 2018 Refresh 503.4 mandates caption controls for AT users. An uncaptioned product demo, testimonial, or tutorial video excludes deaf users entirely from that content. Auto-generated captions from hosting platforms (YouTube, Vimeo) are frequently inaccurate and do not satisfy the synchronization or accuracy standards required by Section 508 procurement evaluators.

For self-hosted video, generate a WebVTT caption file and attach it with a <track> element:

<video controls width="100%">
  <source src="/videos/product-demo.mp4" type="video/mp4" />
  <track
    kind="captions"
    src="/captions/product-demo-en.vtt"
    srclang="en"
    label="English captions"
    default
  />
</video>

For YouTube embeds, ensure the original video on YouTube has accurate captions (not just auto-generated). Validate accuracy—auto-generated captions often fail on proper nouns, technical terms, and accented speech. For Vimeo, upload a .vtt file through Vimeo's caption manager. Use tools like caption.ninja or Otter.ai to generate a first-pass VTT file, then manually correct errors before publishing.