How to add subtitles or captions to a video

Captions make videos watchable on mute, easier to follow, and more accessible. The old way meant typing every line by hand or uploading your footage to a transcription service. With Supercut you type one plain-English prompt, the audio is transcribed on your own device, and the captions are timed to your speech automatically. Your footage never leaves your browser.

Try it in the editor, freeNo upload · No sign-up to start · 100% private

Subtitles vs captions: what you actually want

People use the words interchangeably, and for most short-form video the difference does not matter. Subtitles usually mean a text version of the spoken words, often used for translation. Captions usually mean on-screen text styled for the video, the kind you see in TikToks and Reels where each word pops as it is spoken. Supercut generates spoken-word captions: it transcribes your audio, times each word, and burns the text into the video so it plays the same everywhere, with no separate subtitle file to manage.

How Supercut captions a video

You do not scrub a timeline or type lines into boxes. You drop a clip into the editor, type something like "add captions, big bold style," and an on-device Whisper model transcribes the audio and times the words to your speech. Because transcription runs in your browser through WebAssembly, your video and its audio stay on your machine. Nothing is uploaded to a server. The first caption request downloads the transcription model (about 39 to 74 MB), then it runs locally from there, even offline once the page is loaded.

Styling, fixing typos, and exporting

Pick a caption style built for short-form video, then preview the result before you commit. If the transcription got a name or a term wrong, you can adjust the caption text and restyle before exporting, so typos are easy to fix. When it looks right, export. The captions are baked into the file, ready to post to TikTok, Reels, or Shorts with no extra subtitle track to upload. Pair captions with a 9:16 reframe and a trim and you have a finished short in a few prompts.

Step by step

  1. 1

    Drop your clip into the browser

    Open the Supercut editor and drag in your video. It loads straight into your browser. There is no upload, and you can try your first export without an account.

  2. 2

    Type the caption prompt

    In plain English, type something like "add captions" or "add captions, big bold style." The on-device model transcribes the audio and times each word to your speech automatically.

  3. 3

    Preview and fix the text

    Watch the captioned preview. If a name or word came out wrong, edit the caption text and adjust the style before you commit. Nothing has left your device at this point.

  4. 4

    Export with captions baked in

    Export the clip. The captions are burned into the video file, ready to post to TikTok, Reels, Shorts, or anywhere else, with no separate subtitle file to manage.

Tips

  • Say the style you want in the same prompt, for example "add captions, big bold style," so you skip a step.
  • Captions are timed to your audio, so cleaner sound means cleaner timing. If the recording is noisy, run a noise-removal prompt first, then caption.
  • Proper nouns and brand names trip up any transcriber. Skim the preview and fix those words before exporting.
  • Caption first, then reframe to 9:16, so you can see exactly where the text sits in the vertical frame.

Do it in Supercut

Related use cases

Frequently asked questions

Does adding captions upload my video or audio?

No. Transcription runs on your device with an in-browser model, and the whole edit happens in your browser. Your video and its audio never leave your computer.

Do the captions sync to the words being spoken?

Yes. Supercut times the captions to your speech so each word appears as it is spoken, using caption styles built for short-form video.

Can I fix a typo or a misspelled name?

Yes. You can edit the caption text and restyle it before exporting, so wrong names, terms, or typos are easy to correct.

What languages can it caption?

The on-device transcription model handles a wide range of spoken languages. Accuracy is best with clear audio, so reduce background noise first if the recording is rough.

Are captions free?

You can try your first export with no account. Unlimited watermark-free exports and every tool are part of a paid plan: from 4.99 per month billed yearly (59.88 per year), 9.99 per month on a monthly plan, or 199 as a one-time lifetime purchase. You can cancel anytime.