Add audio to a video
Put a new soundtrack on a clip, replacing or mixing with the original.
- Runs on your device — the file is never sent anywhere
- No sign-up, no watermarks, no daily quotas
- Free, with no limit on how often you use it
How it works
Replacing a soundtrack covers most of what people want from a simple video editor: music over silent footage, a clean voiceover replacing noisy on-camera sound, or a recorded narration laid over a screen capture.
Replace or mix
Replacing discards the original sound entirely, which is what you want for music over silent footage or a re-recorded voiceover. Mixing keeps both, which suits background music under existing speech — though with no level control, loud music will compete with the voice. Lower the music's volume first with the audio volume tool if that happens.
Lengths rarely match
By default the result runs as long as the video: a shorter audio track simply stops, and a longer one is cut off. Choosing to stop at whichever ends first is useful when the music is meant to define the length.
The picture is untouched
Only the audio is re-encoded; the video stream is copied across exactly as it was. That makes this one of the quicker video tools and means no quality is lost from the picture.
Silent videos are handled
Screen recordings and drone footage often have no audio track at all. Mixing has nothing to mix with, so the new track is simply used on its own.
Add audio to a video — questions
Can I keep the original sound as well?
Yes, choose to mix. There is no level control, so lower the new track first if it drowns out speech.
What if the audio is shorter than the video?
It stops and the rest of the video is silent. Choose to stop at whichever ends first if you would rather the video were cut.
Does the picture quality change?
No. The video stream is copied across untouched.
Is my video uploaded?
No. Everything runs in your browser.