How to add subtitlesto a YouTube video

There are three ways to get subtitles onto a YouTube video: let YouTube transcribe it, upload a subtitle file yourself, or publish caption tracks from an app. They differ in accuracy, in how much control you have over the look, and in how much work each extra language costs.

Option 1: YouTube's automatic captions

YouTube transcribes most uploads on its own. Nothing to do, nothing to upload — and nothing to control. Automatic captions have no punctuation to speak of, struggle with names, jargon and accents, and carry no styling at all. They are a fallback, not a caption strategy. You can, however, use them as a starting point: download the automatic track, fix it, and upload the corrected file as your own.

Option 2: upload a subtitle file in YouTube Studio

1. Open YouTube Studio and go to Content, then click the video you want to caption.
2. Open Subtitles in the left menu of the video page.
3. Add a language if the one you need isn't listed yet, then click Add next to Subtitles.
4. Choose how to add them. Upload a file if you already have one, use auto-sync to time a plain transcript against the audio, or type the lines in by hand.
5. Check the timing in the editor and publish.

Studio accepts the usual formats — SRT, VTT, SBV — and also YouTube's own timed-text format, which is the one that carries colours, fonts, positions and per-word timing.

Set the video's original language first. Without it, YouTube doesn't know what the uploaded file is a translation of, and the language list behaves oddly.

Option 3: publish caption tracks from an app

Uploading one file by hand is fine. Uploading the same video's captions in twelve languages, then fixing a typo in all of them, is not. Apps that talk to YouTube's API do the same thing Studio does, in one pass: sign in with Google, pick the video, send every track. That is what Rainbow Captions is for — the styled original and every translation go up together, and replacing a track later is one click.

Which file format to use

• SRT — the universal one. Text and timings, no styling. Use it when the captions just need to be correct.
• VTT — SRT's web sibling; supports some positioning and basic styling, most of which YouTube ignores.
• SBV — YouTube's old plain format; no reason to choose it today.
• YouTube timed text (.ytt) — the only format that survives with colours, fonts, outlines, positions and word-by-word timing intact. This is what styled captions are made of.

Adding a second language

Every language is its own caption track on the same video. Add the language in Subtitles, upload the translated file, publish. Viewers then pick the language in the player's captions menu, and YouTube shows the track that matches their interface language when one exists.

Two things worth knowing. YouTube's automatic translation of your captions is a viewer-side convenience: it is machine translation of your text on the fly, it carries no styling, and you have no control over it. And YouTube's community contributions — where viewers could submit translations for your videos — were discontinued in 2020, so translated tracks now come from you.

When captions don't show up

• Nothing appears after upload. Give YouTube a few minutes to process the track, then reload the watch page rather than the Studio tab.
• The file is rejected. Usually an encoding problem: save as UTF-8, without a byte-order mark.
• The timing drifts. The subtitle file was made for a different cut of the video. Re-export it against the version you uploaded.
• Styling is gone. Colours and fonts only survive in YouTube's timed-text format. An SRT will always render as plain white text on a dark box.
• Captions show for you but not for viewers. Check that the track is published rather than left as a draft, and that the video itself isn't set to "captions off" for the audience by their own player settings.

Questions

How do I add subtitles to a YouTube video I already published?

In YouTube Studio, open the video, go to Subtitles, add the language and upload your file. The video itself is never re-uploaded — captions are a separate track attached to it.

Can I add subtitles in several languages at once?

In Studio you add them one language at a time. Through YouTube's API — which is what caption apps use — the original and every translation can be published in a single pass.

Do subtitles help a video get found?

A caption track is text YouTube can read, in every language you publish, which is more than a burned-in caption gives you. It also makes the video usable for viewers who watch without sound or don't speak your language — which is usually the bigger win.