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Add Audio to Video

Replace or add a new audio track to your video with volume control. Perfect for adding background music or voiceovers.

Free to use, no watermarks, runs in your browser—nothing uploads to our servers

Source file

Files are processed locally in your browser using WebAssembly.

Saved FFmpeg presets (stored locally)

Saved presets

Preset name

Note: This tool requires uploading both a video and audio file. Current implementation is limited to single file input. Use desktop video editing software for adding audio tracks.

Audio Volume

1.0 = normal, 0.5 = half volume, 2.0 = double

Jump to helper sections

What happens to the original audio?

The original video audio is replaced with the new audio track. If you want to keep the original audio, first extract it and mix it separately.

What if audio is longer than video?

The output will match the video length. Longer audio will be truncated, shorter audio will result in silence at the end.

Can I adjust audio volume?

Yes! Use the volume control to make the audio louder (>1.0) or quieter (<1.0). Value of 1.0 keeps original volume.

Report a bug

If this tool misbehaves, share a quick summary so we can investigate. We include the tool URL automatically—no need to copy and paste.