Drop a video here, or click to select
Drop an audio file here, or click to select
Delay before the added audio begins in the video.
Leave empty to use the rest of the audio file.
Processing runs locally in this browser tab. Large or long videos require more memory and time.
Add music, narration, sound effects, or a replacement soundtrack to a video. You can mix both sources, mute the original sound, or, when the source has sound, keep two separate audio tracks.
Mix creates one soundtrack that combines both sources. Replace removes the original sound. When the source video has sound, separate mode keeps both audio tracks so a compatible player can switch between them.
Yes. Enable looping to repeat the selected audio segment until the video ends. Without looping, the added audio stops when it ends; if the original sound is retained, it continues for the rest of the video.
WebM input downloads as WebM. Other supported videos download as MP4, a format widely supported by browsers, phones, and desktop players.
The selected files are processed in this browser tab and are not uploaded to a server by this tool. Device memory and performance determine the practical size limit.
Related tools: Video Mute · Video Trimmer · Audio Editor