PostEaseThe short answer
Captions are the words of a video shown as text on screen. Closed captions are a separate track the viewer can switch on or off; open captions are part of the picture itself, so they always show, wherever the video is posted.
The W3C’s Web Accessibility Initiative puts the difference in two sentences: most captions are “closed captions” that can be hidden or shown by people watching the video, and they can be “open captions” that are always displayed and cannot be turned off.
Captions, in the W3C’s words
From the W3C Web Accessibility Initiative’s page on captions and subtitles:
| Term | What the W3C says |
|---|---|
| Captions | Captions are a text version of the speech and non-speech audio information needed to understand the content. |
| Closed captions | Most are “closed captions” that can be hidden or shown by people watching the video. |
| Open captions | They can be “open captions” that are always displayed and cannot be turned off. |
| Subtitles | Subtitles/interlingual subtitles are usually only the spoken audio (for people who can hear the audio but do not know the spoken language). |
Open or closed
Each kind suits a different place:
| What differs | Open captions | Closed captions |
|---|---|---|
| Can viewers turn them off | No, they are part of the picture | Yes |
| Survive a repost or download | Yes, they travel with the video | Only where the caption file goes too |
| Can be styled in your look | Yes, any font, colour and position | Shown in the player’s own style |
| Can be edited after posting | No, the video has to be exported again | Yes, by replacing the file |
| Other languages | One language per video | Several tracks, one per language |
What the accessibility standard asks
The Web Content Accessibility Guidelines, the W3C’s standard for accessible web content, make captions a Level A requirement, the most basic level. Success Criterion 1.2.2 reads: “Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.” Its stated intent is “to enable people who are deaf or hard of hearing to watch synchronized media presentations.”
Which to use on social media
Short video is mostly watched on phones, often with the sound off, and it is reposted and downloaded, so open captions styled to read at a glance are the usual choice for Reels, TikTok and Shorts. Closed captions suit long videos on YouTube, where viewers expect to switch them on, and where a separate file can carry several languages.
Either way, captions written by a machine need a read-through. The W3C is blunt about it: its page is headed “Automatic Captions are Not Sufficient”, because misheard words and missing punctuation change what a viewer understands.
YouTube says the same of its own: automatic captions “might misrepresent the spoken content due to mispronunciations, accents, dialects, or background noise,” and creators “should always review automatic captions and edit any parts that haven't been properly transcribed.”
Adding closed captions on YouTube
YouTube’s Help Center lists four ways to add them in YouTube Studio, under Subtitles: upload a file, auto-sync a transcript you paste in, type them manually, or auto-translate. YouTube notes that “Automatic captions will be in the video’s default language only.”
Captions in PostEase
Studio, the video editor in PostEase, writes captions from what is said in your video. You can restyle them, pick out key words, and fix a misheard word everywhere at once.
Questions
What is the difference between open and closed captions?
Closed captions can be turned on and off by the viewer; open captions are part of the video and always show.
Are captions the same as subtitles?
Not quite. Captions carry speech and the sounds needed to follow the video; subtitles are usually only the speech, often translated, for people who can hear but do not know the language.
Which captions work best on TikTok and Reels?
Open captions, styled to read at a glance, since much short video is watched without sound and reposted where a caption file would not follow.
Are automatic captions good enough?
Not without a check. The W3C’s guidance is that automatic captions are not sufficient on their own; read them through and fix misheard words.
Sources
- W3C, Captions/Subtitles (Web Accessibility Initiative), checked October 2026.
- YouTube, Add subtitles & captions, checked October 2026.
- YouTube, Use automatic captioning, checked October 2026.
- W3C, Understanding Success Criterion 1.2.2: Captions (Prerecorded), checked October 2026.