Where does the music come from?

You provide it — upload any audio file from your own device. This tool doesn't include a music library, so you're always in control of what you have the rights to use.

Am I allowed to use any song I want?

Only use audio you have the rights to use — a track you created, licensed, or that's explicitly royalty-free. Copyright holders (and platforms like YouTube and Instagram) can still flag or mute unlicensed music even if you added it yourself.

What happens if the music is longer or shorter than my video?

The music loops automatically if it's shorter than the video, and gets trimmed to the video's length if it's longer — your output is always exactly as long as the original video.

Is my video or audio uploaded anywhere?

No — mixing happens entirely in your browser using FFmpeg compiled to WebAssembly.

Add Music to Video

Mix your own music or audio file into a video, or replace its original audio entirely.

Runs entirely on your device— nothing is uploaded, so processing uses your own CPU and memory. Large files can take a while (don't worry, it hasn't frozen), and very large files may be slow or crash the tab on phones — for big files, use a desktop or laptop.

Want to combine this with other edits? Try the full Video Editor

Processed 100% in your browser — nothing you enter here is ever uploaded.

Common use cases

Adding background music to a silent clip

Screen recordings and silent B-roll often need a music bed before posting to Reels or Shorts.

Adding a voiceover over muted footage

Replace a video's original audio with a separately recorded voiceover track.

Layering trending audio under your own footage

Mix a downloaded audio clip under your video's existing sound at a lower volume.

How to use the Add Music

Drop in a video, then drop in a music or audio file from your own device.

Choose whether to mix the music with the video's original audio, or replace it entirely.

Adjust the music and original audio volume with the sliders, then click Add music.

If the music is shorter than your video, it loops automatically to fill the whole length.