Add or Replace Audio in Video

Easily add new audio to your video (mixing with original sound) or completely replace the video's existing audio. Keeps original video length. Option to loop shorter audio. Adjust added audio volume in dB.

Loading Processing Engine (FFmpeg) 0%

Initializing...

About Add or Replace Audio in Video

Use our Free Online Add or Replace Audio in Video Tool to easily add music or a voiceover to your videos by mixing it with the original sound, or to completely replace the video's existing audio track. If your video has no sound initially, the new audio is simply added. The final video will always match the length of your original video.

If the audio track you're using is shorter than your video, you can choose to play it once or have it loop to cover the entire video duration. Longer audio tracks will be trimmed to fit the video's length. You can precisely adjust the volume of the new audio track using a decibel (dB) scale. All processing happens directly in your browser for speed and privacy – no file uploads!

Features:

Add or Replace Audio: Choose to mix new audio with the video's original sound or replace the original audio entirely.
Mix with Original Sound (Add Mode): If you choose to 'Add', and your video already has audio, it will be mixed with the new track. The original audio plays at its normal volume.
Replace Original Sound (Replace Mode): If you choose to 'Replace', the video's original audio track is removed and replaced with your new audio.
Matches Video Length: The output video duration will be identical to your original video's duration. Audio is trimmed or looped as needed.
Loop Option for Shorter Audio: If the new audio track is shorter than the video, you can choose to loop it to fill the entire video length, or play it just once.
Volume Control for New Audio (dB): Adjust the loudness of the new audio track (whether adding or replacing) using a decibel (dB) scale (0dB is original volume of the new track).
Client-Side Processing: Securely processes files in your browser using FFmpeg.wasm. No uploads required.
Wide Format Support: Works with common video (MP4, WEBM, MOV) and audio (MP3, WAV, AAC) formats.
Previews: Preview your original video, the new audio track, and the final video with the modified audio.
MP4 Output: Download your video with the new/modified audio in the widely compatible MP4 format.
Progress Tracking: See the progress of the audio processing in real-time.

How to Use:

Load Engine: Wait for the FFmpeg processing engine to load.
Upload Video: Select or drag & drop your video file.
Upload New Audio: Select or drag & drop the audio file you want to use.
Configure Audio Settings:
- Select Audio Action:
  - Choose 'Add to Video (Mix)' to combine the new audio with the video's original sound.
  - Choose 'Replace Video's Audio' to use only the new audio, removing any original sound from the video.
- Adjust the Volume for New Audio using the dB slider (0dB makes no change to the new track's volume).
- If the new audio is shorter than the video, choose whether to "Play Once" or "Loop Audio".
Process: Click the "Process Video" button.
Wait & Preview: Monitor progress. Once complete, preview the video with the modified audio.
Download: Save your final video.
Share (Optional): Share a link to this tool.

Note: Processing happens entirely in your browser. Larger files or longer videos may take more time and consume more system resources. The video will be re-encoded to incorporate the audio changes.

Reference this content, page, or tool as:

"Add or Replace Audio in Video" at https://MiniWebtool.com/add-replace-audio-in-video/ from MiniWebtool, https://MiniWebtool.com/

by miniwebtool team. Updated: May 26, 2025