Closed Captions

Closed captions vs subtitles

The two words are often used interchangeably, and in British English "subtitles" commonly covers both. The distinction that matters is who the text is written for.

	Closed captions	Subtitles
Written for	Viewers who cannot hear the audio	Viewers who can hear but do not understand the language
Content	Dialogue, speaker names, sound effects, music cues: "[door slams]", "[upbeat music]"	Dialogue only, usually translated
Language	Usually the same language as the audio	Usually a different language
Can be turned off	Yes (closed) or no (open)	Yes, when delivered as a track

SDH (subtitles for the deaf and hard of hearing) combines the two: subtitles that also describe sounds and identify speakers. A marketing team can produce one same-language caption track and several translated subtitle tracks for the same video.

SRT and WebVTT files

Caption tracks are usually stored as plain-text files that list cues: a start time, an end time and the text to show.

	SRT (SubRip)	WebVTT (.vtt)
Origin	The SubRip program; a de facto format with no formal standard	Specified by the W3C as the Web Video Text Tracks Format
First line	A cue number	The signature WEBVTT
Timestamp	00:01:12,500 --> 00:01:15,000 (comma)	00:01:12.500 --> 00:01:15.000 (full stop)
Styling and position	Very limited	Cue settings for position and alignment, CSS styling, speaker voices
Browser playback	Not supported by the HTML <track> element	The format HTML <track> elements play
Typical use	Editing software, stock footage, social platforms	Web players, HLS streams, embeds

An SRT file is the most widely accepted format for uploading captions to editing tools and social networks. A browser, however, only plays WebVTT through the <track> element, so web players convert SRT to WebVTT before playback. Converting between the two is lossless for the text and the timing.

Captions and accessibility rules

The Web Content Accessibility Guidelines (WCAG) 2.2, a W3C Recommendation published in October 2023, set the reference requirements for video on the web:

• Success criterion 1.2.2 Captions (Prerecorded), level A: captions are provided for all prerecorded audio content in synchronised media, unless the media is clearly labelled as an alternative for text.
• Success criterion 1.2.4 Captions (Live), level AA: captions are provided for all live audio content in synchronised media.
• Success criterion 1.2.1 Audio-only and Video-only (Prerecorded), level A: prerecorded audio-only content, such as a podcast, needs a text alternative, usually a transcript.

In the EU, the Web Accessibility Directive (EU) 2016/2102 requires public sector websites and apps to meet the European standard EN 301 549, which incorporates these WCAG criteria, and the European Accessibility Act (Directive (EU) 2019/882) has applied to many consumer-facing products and services since 28 June 2025. For B2B marketing teams, the practical point is simpler: a product video on the website, an onboarding video for customers or a recorded webinar without captions excludes part of its audience and may breach the organisation's own accessibility commitments.

Captions in day-to-day marketing work

• Social video. Many viewers watch feeds with the sound off, so captions carry the message. Burned-in open captions suit platforms that do not accept caption files; closed captions suit everything else.
• Localisation. One master video with an English caption track and translated subtitle tracks replaces separate exports per country. See global branding.
• Search. A caption file contains every spoken word, which makes a video findable by what is said in it.
• Review. Legal and brand reviewers read claims in the caption track faster than they can scrub through the video.

Common mistakes: auto-generated captions published without checking product names; captions that only transcribe speech and leave out sounds that matter; and translated subtitles made from a draft script instead of the final cut.

Closed captions in Freedam

• Speech in videos is transcribed automatically at upload, and the transcript becomes a caption track marked Auto. See transcription.
• Editors can upload SRT or VTT files, one track per language, label each track and choose the default one. SRT files are converted to WebVTT for playback.
• A transcript editor shows the video next to the list of cues: click a timestamp to jump there, correct the text and save. Tracks download as VTT, SRT or plain text.
• A track can be translated into another language with the workspace's translation provider, creating a new track marked Translated. The Glossary page in the administration lets administrators give the preferred spellings of brand and product names for transcription and translation.
• Captions play in the player's caption menu on the asset page, in share links and in video embeds on other websites.
• The text of every track is indexed for search, so typing a phrase spoken in a video finds it. Translated tracks are found by searches in their own language. See video poster and subtitles.

Frequently asked questions

What is the difference between closed captions and subtitles?

Closed captions are written for viewers who cannot hear the audio and include sound effects and speaker names. Subtitles are written for viewers who can hear but need a translation, and contain dialogue only.

What is an SRT file?

An SRT (SubRip) file is a plain-text caption file. Each cue has a number, a start and end time with a comma before the milliseconds, and one or more lines of text. It opens in any text editor.

Are automatic captions enough for accessibility?

They are a starting point. Automatic transcription misspells names and jargon and does not describe sounds, so captions should be reviewed and corrected before a video is published.