The short answer
Subtitles assume the viewer can hear but doesn't understand the language, so they show the dialogue, often translated. Captions assume the viewer can't hear the audio, so they show the dialogue and also important sounds, like [music] or [door slams], and who is speaking.
On Reels, TikTok and Shorts, “captions” usually just means the words of the speech on screen, styled and timed to the voice, because most people watch with the sound off.
The terms, side by side
| Term | What it means | Can the viewer turn it off? |
|---|---|---|
| Subtitles | The dialogue as text, usually for viewers who don't speak the language | Usually |
| Captions | The dialogue plus meaningful sounds, for viewers who can't hear it | Depends on the type |
| Closed captions (CC) | Captions in a separate track or file the player shows on request | Yes |
| Open (burned-in) captions | Captions drawn into the video picture itself | No |
| Auto captions | Captions generated automatically from the speech by speech recognition | Depends on the type |
| SDH | Subtitles for the deaf and hard of hearing: subtitles that include sound descriptions | Usually |
What auto captions are
Auto captions are made by speech recognition: software listens to the audio and writes down the words with their timing. YouTube, Instagram and TikTok can all generate them in their own players, and tools like CAPWAV generate them so you can style and burn them into the video.
Automatic transcription is very good on clear speech, but it still mishears names, brands and rare words. Read the captions once before you post, and fix what's wrong. In CAPWAV you click a word to correct it.
Making either with CAPWAV
CAPWAV turns the speech in a video into word-timed text in 90+ languages. From there you can export the video with captions burned in, in any of the caption styles, or download the same text as SRT or VTT subtitles, free on every plan. On the Creator and Pro plans the captions can be translated into 75 languages as they're made.
Start with the subtitle generator if you need a file, or the auto caption generator if you want styled captions on the video.