UseTool

Replace the audio of a video

Take the picture from one file and the sound from another. Everything happens on your device.

Video

New audio

The video sets the length. Longer audio is cut off, shorter audio ends in silence.

🔒 Your files never leave your device.

How it works

How it works

  1. 1

    Add what goes in

    Add a video and an audio file together — the tool needs both before it can start.

  2. 2

    Start it

    Set which sound file replaces the old one, then start. Everything runs in this browser — no upload, no queue, no account.

  3. 3

    Take the result

    The MP4 · WebM is ready the moment the run finishes. Save it straight to your device.

What this tool does

Replace the audio of a video
Throws the original sound away and puts a new track in its place — a voice-over, a dub, a cleaned-up recording. One video, one audio file; the picture is untouched by the exchange.

When you need this

  • Wind noise ruins the sound of a drone flight that should have music instead.
  • A narration recorded separately should replace the camera's own sound.

Good to know

Frequently asked questions

What files can I use here?

Needs a video and an audio file together.

What do I get back?

You get MP4 · WebM.

Does the file lose quality?

Every frame is decoded and encoded again. That is what makes the file smaller or different — and it costs some detail, most visibly in fast motion and fine texture.

When does it not work?

Which video codecs work depends on your browser. Chrome and Edge read the most, including H.265 on many machines; Safari and Firefox refuse some. A file that will not open here usually opens in Chrome.

Does the video lose quality?

Only when it has to be re-encoded. Cutting, joining and removing the sound track copy the picture data unchanged, so those are lossless. Compressing and adding a watermark do re-encode, which is why they take longer.

How long may a video be?

There is no fixed limit. What decides is the memory of your device: a phone manages a few minutes comfortably, a computer handles far more. If a long video fails, splitting it first and working on the parts usually helps.

Private by design

Your files stay on your device

Your files never leave your device.

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Ready-made

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