Add captions to a video, automatically, on your device

Add accurate, styled captions without sending your footage to a server. Supercut transcribes your audio on your own device and burns in word-perfect captions, so your video and its audio never leave your browser.

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Add captions, big bold style

Works with

MP4MOVWebM

How it works

  1. 1

    Drop your clip

    Load your video into the editor. Everything happens locally, so there is nothing to upload and nothing to wait on a server for.

  2. 2

    Ask for captions

    Say “add captions” and pick a style. Supercut transcribes the audio on-device and times each word automatically.

  3. 3

    Export with captions baked in

    Preview the captioned clip, tweak the style if you like, and export, captions burned in, ready for TikTok, Reels or Shorts.

Tips

  • Pick a bold style for sound-off autoplay feeds.
  • Fix names and jargon in the caption text before exporting.
  • Keep lines short so captions do not cover the subject.

Why it stays private

Supercut decodes, edits and exports your video entirely in your browser with WebAssembly. Your footage is never uploaded, the only thing that leaves your device is the text of your prompt, so the AI knows what edit to plan. Read more in our Privacy Policy.

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Who uses this

Frequently asked questions

Does captioning upload my audio?

No. Transcription runs on your device with an in-browser model. Your audio and video never leave your computer.

Do the captions sync to the words?

Yes. Supercut times captions to your speech so words appear as they are spoken, with caption styles built for short-form video.

Can I edit the caption text?

You can adjust the captions and restyle them before exporting, so typos or names can be fixed.

Ready to try it?

Drop a clip and describe the edit, it runs right here in your browser.

Open the editor