Replace Audio Track in Video
Free online tool to replace or add audio track to video. Change video audio, add music to video, replace soundtrack. Supports MP4, WebM, MOV.
About Replace Audio Track
This online tool allows you to replace or add audio tracks to video files directly in your browser. Perfect for adding background music, replacing commentary, or fixing audio issues. All processing happens locally for complete privacy.
What file formats are supported?
Video: MP4, WebM, MOV. Audio: MP3, AAC, WAV, OGG, FLAC, and other common audio formats.
Can I add music to a video without audio?
Yes! You can add audio to videos that don't have an audio track, or replace the existing audio with new audio.
What if the audio is shorter than the video?
You can choose to loop the audio to match the video length, or leave it as-is (video will be silent after audio ends).
What if the audio is longer than the video?
You can choose to trim the audio to match the video length, or keep the full audio (video will end while audio continues in some players).
Will this affect video quality?
No, the video stream is copied without re-encoding, preserving 100% original video quality. Only the audio is processed.
Is my data safe?
Absolutely! All processing happens directly in your browser using FFmpeg.wasm (WebAssembly). Your files are never uploaded to any server. Everything stays private on your device.
Can I preview before downloading?
Yes! After processing, you can preview the video with the new audio track before downloading.
How long does processing take?
Processing time depends on video length. Since we're copying the video stream (not re-encoding), it's typically fast - usually 10-30 seconds for a 5-minute video.