Subtitling, Captions and SDH Services

Subtitle translation is more than a translated transcript

This is the part clients are most often surprised by. A subtitle is not a sentence of translation with a timestamp attached to it. A viewer can only read so fast, and a subtitle box can only hold so much, so the subtitler has to carry the meaning in fewer words than the speaker used. English speech runs at roughly 150 words a minute; comfortable reading on screen, while also watching the picture, runs a good deal slower.

Subtitle translation is therefore translation plus editing plus timing, done by someone who thinks in cues rather than paragraphs. Cut the wrong word and a legal disclaimer stops meaning what it said. Cut nothing and the viewer is still reading line two as the speaker starts the next sentence. It is the same discipline behind our wider translation services, applied under a stopwatch: where a document translator can add a clarifying clause, a subtitler has to lose one and keep the sense intact.

Reading speed, line length and timing discipline

Most subtitle style guides converge on the same handful of rules, and the rules exist for comprehension rather than tidiness.

• Two lines maximum on screen at once, typically around 37 to 42 characters per line depending on the platform.
• A reading-speed ceiling, usually expressed in characters per second, so nothing flashes past before it can be read.
• A minimum duration on every cue, so a one-word answer does not blink.
• Line breaks placed at a grammatical join rather than wherever the character limit happens to fall. "The chief executive of the / company resigned" reads badly; "The chief executive of the company / resigned" reads fine.
• Cues timed to the speech and, where possible, respecting shot changes so the text does not straddle a cut.

Broadcasters and streaming platforms each publish their own numbers, and we work to whichever applies to your job rather than to a house style of our own. Ofcom's guidance on subtitle quality is the reference point for UK broadcast. Tell us the destination and we will follow its style guide.

SRT and VTT subtitle files, or burned-in subtitles

The finished job is a file, and the right file depends on where the video is going. SRT is the plain workhorse that almost every web player and social platform accepts. VTT is the HTML5 standard, and carries a little more styling and positioning information. SBV is YouTube's own variant. TTML and EBU-STL are what a broadcaster or post house is usually asking for when it asks for "the subtitle file".

If your platform will not carry a sidecar file at all, we can supply burned-in subtitles instead. Decide that before the work starts rather than after, because burned-in text cannot be corrected without a fresh export and every extra language means another version of the video. Send the platform, the player or the broadcaster's delivery spec with your enquiry and you will get files that drop straight in.

Foreign language subtitling in 300+ languages

Foreign language subtitling goes to a translator who is a native speaker of the target language and who has subtitled before. Those two things are not the same skill: a strong document translator can produce subtitles that are perfectly accurate and completely unreadable at speed.

Both directions are routine. A recorded patient information film going out as Polish translation services for an NHS trust, or evidential footage needing Arabic translation for a firm of solicitors, both start the same way. The full language list is worth a look if yours is unusual, and if the video is part of a broader product or course, localisation covers the on-screen text and interface strings that sit around it.

Why UK organisations add closed captions to video

Some of it is duty and some of it is reach. Most organisations arrive here for one reason and stay for the other.

On duty: the Equality Act 2010 requires reasonable adjustments, and public sector bodies in the UK also sit under the Public Sector Bodies (Websites and Mobile Applications) Accessibility Regulations 2018, which point at the WCAG 2.1 AA standard. That standard asks for captions on prerecorded video. An NHS trust publishing a patient information film, a council explaining a consultation, a university putting lectures online: all of them are on the hook, and an auto-generated caption track that mangles clinical terms does not discharge it.

On reach: a large share of social video is watched with the sound off, on a train or in an open-plan office, and captions are the only reason those viewers stay. Caption text is also indexable, which makes video findable in a way a silent thumbnail never will be. Captions help anyone watching in a second language too, or trying to catch an unfamiliar name the first time they hear it.

What drives the cost of subtitling

We price per job rather than off a rate card, because the same ten minutes of video can be an easy afternoon or a genuinely hard week. Four things move the number.

• Runtime. The single biggest factor. Subtitling time scales with the length of the finished cut, not the length of the rushes.
• Number of languages. The first language carries the cueing and timing work. Additional languages reuse that timing, so the second and third cost less per language than the first.
• Whether a transcript exists. An accurate, checked transcript removes a whole stage. A rough auto-generated one usually does not, because correcting it takes about as long as typing it.
• Audio and picture condition. Clean dialogue with one speaker at a time is quick. Crosstalk, heavy background noise, or an edit that is still moving all add hours.

Deadline sits on top of all four. Genuinely urgent work carries a premium, and we will tell you honestly if waiting a day would save you money. Our pricing page sets out how we price language work generally; for video the only sensible answer is a quote against your actual runtime and language list.

Need a plain transcript instead?

Not every video needs captions on screen. If what you actually want is a written record you can read, search and quote from, that is transcription rather than subtitling. Our video transcription page covers footage, and audio transcription covers interviews, meetings and dictation with no picture attached. A transcript is also cheaper, and for a lot of internal jobs it is all anyone was ever going to read.