Add audio to video
Put music or a voice-over on a video: replace its sound or mix with it, set each volume, and loop the sound to the end.
Drop a video here
MP4, MOV, WebM or MKV. Up to 1.0 GB per file.
Runs in your browser. Your files are not uploaded.
Large videos can run out of memory on phones.
Changing the picture uses your browser's own video encoders. Recent Chrome and Edge can write H.264, VP9 and AV1; Firefox and older Safari lack some encoders, so the tools offer only what your browser can produce and say so when something is missing.
Need only the soundtrack? Extract audio with the audio tools.
How to use Add audio to video
Choose a video or drop it on the page.
Drop the audio to add: MP3, M4A, WAV, OGG, FLAC or another video.
Pick Replace or Mix, and Loop or Play once.
Set the volumes in percent, then select Add the audio.
Download the result.
Questions
Longer sound is cut where the video ends. Shorter sound is repeated with Loop, or followed by silence with Play once.
Not when the video's format can hold it as it is, which is usual. Then the picture is copied and keeps its quality; only the sound is encoded.
No. Everything runs in your browser on your own device, and neither the video nor the sound is uploaded.
Related tools
- Video cutter (trim video)Cut a video to the part you want, with a preview and buttons to mark the start and end.
- Resize videoScale a video to 1080p, 720p or 480p, or fit it to a square, portrait or landscape frame.
- Rotate and flip videoTurn a video by 90 degrees or mirror it horizontally or vertically.
- Mute videoRemove the sound from a video and keep the picture untouched.