Guide
Captions vs subtitles: what is the difference?
By Rakshit · Updated
Captions are a text version of the speech and the sounds needed to follow a video. Subtitles, in W3C's usage, are a translation of the speech for viewers who can hear it but do not understand the language. Closed captions can be switched off; open captions are always on screen. For a short clip posted on social apps, burned-in open captions are the usual choice.
The short version
The two words overlap, and which one people use depends on where they live. W3C's accessibility guidance uses captions for text in the same language as the audio and subtitles for spoken audio translated into another language. It adds that some regions use subtitles for both. WCAG, the web accessibility standard, notes the same thing: in some countries captions are called subtitles.
The thing that really separates them is the job. Captions exist so that someone who cannot hear the audio can follow everything: W3C describes them as text for the speech and the non-speech audio needed to understand the content. Subtitles assume the viewer can hear, and translate or transcribe the dialogue. W3C says captions are needed for accessibility, whereas subtitles in another language are not directly an accessibility accommodation.
One table for all the terms
| Term | What it is | Includes sound cues? | Can the viewer turn it off? |
|---|---|---|---|
| Captions | Text of the speech plus non-speech audio needed to understand the video, in sync with it | Yes, such as sound effects, music and who is speaking | Depends on whether they are closed or open |
| Subtitles (W3C usage) | Spoken audio translated into another language | Usually not: W3C says subtitles are usually only the spoken audio | Depends on how they are delivered, as with captions |
| Closed captions | Captions the viewer can show or hide | Yes | Yes, in players that allow it |
| Open captions | Captions drawn into the picture, for example as images of text in the video | Yes, if the maker included them | No, they cannot be turned off |
| Burned-in or hardcoded | Captions or subtitles drawn into the video file. This page uses the term for open captions | Whatever the maker put there | No |
WCAG makes the dialogue point precisely: captions are similar to dialogue-only subtitles, but they also convey non-dialogue audio such as sound effects, music, laughter and speaker identification.
Closed captions versus captions
This is the other half of the question people search. Captions is the general idea. Closed is a delivery choice. W3C says most captions are closed, meaning the viewer can hide or show them, and that captions can also be open, meaning always displayed and impossible to turn off. So every set of closed captions is captions, but not every caption is closed.
In United States rules for television, the legal term is closed captioning, defined in 47 CFR 79.1 as the visual display of the audio portion of video programming. The same rule says open captioning or subtitles in the language of the target audience may be used in place of closed captioning. Those TV rules are about programming that airs on TV, so do not read them as a rule for your own clips.
Under the hood a caption track and a subtitle track are built the same way. W3C says subtitles are implemented the same way as captions, and the HTML Standard separates the two kinds only by purpose: subtitles are for sound that is available but not understood, captions for sound that is unavailable or unclear. If you leave the kind out of an HTML track element, it defaults to subtitles.
Which to use on a short clip
- Posting a vertical clip to TikTok, Reels or Shorts: use open, burned-in captions. They are part of the picture, so they show wherever the video plays, and you control how they look. The cost is that viewers cannot hide them.
- Uploading a long video to a site or player that takes a caption file: upload a closed caption track and let viewers choose. See SRT vs VTT for the file formats.
- Reaching viewers in another language: add subtitles in that language. Write them as a translation, not a copy of the English text.
- Accessibility is the goal: include sound cues that matter and make sure the text is accurate. W3C says automatic captions do not meet accessibility requirements unless confirmed fully accurate.
Which one KeyMo uses
KeyMo's captions are burned in, so they are open captions in the sense above: part of the picture, always on, in one of 12 styles or none. Clips come out at 1080x1920, 9:16, with no watermark on any plan. This page does not claim that KeyMo exports a separate caption file, so if you need a closed caption track for a platform, you will need another tool for that step.
Because open captions cannot be hidden, readability is on you. WCAG says captions should not obscure or obstruct relevant information in the video. For talking-head clips that means keeping the text off the speaker's mouth. For more on the looks, see word-by-word captions and the captions on TikTok guide.
Sources: W3C WAI: Captions/Subtitles (checked 11 October 2026); W3C: Web Content Accessibility Guidelines (WCAG) 2.2 (checked 11 October 2026); WHATWG HTML Standard: media elements and the track element (checked 11 October 2026); eCFR: 47 CFR 79.1 Closed captioning of televised video programming (checked 11 October 2026).