Add Audio to Video Online

Put music or a voiceover under your video. Replace the original track or mix them together.

Drop a video here, or click to browse

Up to 1GB each · MP4, MOV, WebM or MKV

Choose file

Processed locally in your browser. Nothing is uploaded.

Settings

Add a video and the settings for this tool appear here.

How it works

Processed locally in your browser. Nothing is uploaded.

Three steps

How to add audio to a video

No sign-up, no upload queue, no watermark. Everything happens on your device.

1
Drop your file
Drop your video, then add the audio file (MP3, M4A, WAV, etc.).
2
Choose settings
Choose Replace to swap the soundtrack or Mix to blend it with the original.
3
Download
Merge and download. The video track is copied without re-encoding.

Keep going

FAQ

What happens if the audio is longer than the video?

The output ends with the shorter of the two, so the audio is trimmed to the video length.

Does the video quality change?

No. The video stream is copied as-is; only the audio is encoded.

Which audio formats can I add?

MP3, M4A/AAC, WAV, FLAC, OGG and most other common formats.

Desktop · Coming soon

The desktop app is in development. Join the waitlist for launch updates.