Video Add Audio
Add audio to video online for free. Replace or mix audio tracks with video files directly in your browser.
How do I add audio to a video?
Upload your video and audio files, choose mix or replace mode, adjust the timeline if needed, then click Add Audio to process.
What is the difference between replace and mix mode?
Replace mode removes the original audio track and uses only the new one. Mix mode combines both the original and new audio tracks together.
Is my data safe and private?
Yes, all processing happens locally in your browser. No video or audio files are uploaded to any server, ensuring complete privacy.
How do I control when the audio starts and ends?
Use the Audio Start and Audio End sliders in the Timeline section to precisely control when the audio plays within the video duration.
What does the loop audio option do?
When enabled, the audio will repeat continuously if it is shorter than the selected video segment, ensuring uninterrupted audio throughout.
What video and audio formats are supported?
The tool supports all major formats that your browser can handle, including MP4, WebM, MOV for video and MP3, WAV, OGG, AAC for audio.
Can I add audio to a video without the original sound?
Yes, use Replace mode to completely remove the original audio track and substitute it with your new audio file.
Is there a file size limit?
Since all processing happens in your browser, the limit depends on your device's available memory. Larger files may take longer to process.
Can I preview the result before saving?
Yes, after adding audio you can preview the merged result directly in the browser before downloading the final video file.
Do I need to install any software?
No, this is a completely browser-based tool. No software installation, registration, or account creation is required.
How to Use Video Add Audio
Give any video a new soundtrack: replace its original audio entirely or mix the two tracks together. The whole conversion runs locally in your browser, so your files are never uploaded.
- Select the video clip you want to score from your device.
- Choose the audio file that should play over it.
- Pick Replace mode to discard the original track, or Mix mode to layer both sounds.
- In Mix mode, balance the two volume levels so speech and music stay clear.
- Start the render, wait for the local processing to finish, and download the new video.
Lower the original track's volume before mixing if it contains speech you want to keep intelligible.
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