Replace Audio Track
Swap a video's audio for a new audio file. Drop in a video and an audio file (any order).
About Replace Audio Track
Replace Audio Track swaps a video's existing sound for a new audio file — just drop in a video and an audio file in any order. It's the fast way to dub a clip, lay down a music bed, or attach a clean voiceover. Both files are processed in your browser and never uploaded.
- Category
- media
- Input
- Accepts: video/* or audio/*.
- Output
- Outputs: video/mp4.
- Cost
- Free, runs in your browser
- Memory
- high
- Install group
- ffmpeg
Common uses
- Replace a noisy on-camera recording with a clean studio voiceover
- Add a licensed music track to a montage that was filmed silent
- Dub a clip into another language by muxing in a translated voice recording
- Swap raw camera audio for a separately recorded lavalier or shotgun-mic track
- Drop a podcast-style narration over screen-capture footage
Frequently asked questions
Do I need to mute the video first?
No. The tool replaces the existing audio with your new file in one step, so the original sound is dropped automatically.
Does the order of the two files matter?
No — drop the video and the audio file in either order and the tool sorts out which is which.
What audio formats can I use for the new track?
Common audio formats are accepted (audio/* input), including MP3, WAV, M4A, and OGG.
What happens if the audio is shorter or longer than the video?
The output is an MP4 that muxes the new audio against the video; mismatched lengths mean the audio simply ends or the video continues silent, so trim either source first if you need an exact match.
Are my files uploaded anywhere?
No. Both the video and audio stay on your device — the muxing runs locally in the browser.
Keywords
- video
- audio
- replace
- dub
- soundtrack
- mux
- music
- voiceover