Closed caption generator

Closed captions, subtitles and open captions

The three get used interchangeably, but they are not the same thing. Closed captions (CC) are a separate file the viewer can turn on or off, and they transcribe the language actually being spoken. Subtitles usually mean a translation into a different language. Open captions are burned permanently into the video image and cannot be switched off.

This tool produces the first two: a separate, switchable caption file, either in the spoken language or translated. It does not burn captions into video, which is deliberate — a separate file stays editable, is read by search engines, and can be swapped without re-encoding.

Why closed captions matter beyond accessibility

Accessibility is the obvious reason, and in many contexts a legal one: WCAG 2.1 Level AA requires captions for prerecorded audio content, and public-sector and education bodies in a number of jurisdictions are held to it.

The less-discussed reason is reach. A large share of social video is watched with sound off, and caption files are machine-readable in a way that speech is not — platforms index caption text, which makes a captioned video findable by what was said in it.

Which format to upload where

All three come from the same job at no extra cost. Generate once, export whichever you need, or all of them.

• YouTube, Vimeo and most LMS platforms accept SRT — use this unless you have a reason not to.
• HTML5 <track> elements and web players require VTT (WebVTT).
• TXT is a plain transcript with no timings, for show notes, blog posts or documentation.

Editing before you publish

Captions are shown in an editor with the audio, so you can correct recognition errors and adjust block boundaries before exporting. Names, technical terms and numbers are worth a specific check — they are where automatic recognition is weakest and where an error is most obvious to a viewer.