Add Audio to Video
Add custom audio to a video locally in your browser and download MP4. No upload, no signup.
Drop a video to add audio
Select one local video, add one local audio file, and export MP4.
Up to 1 files · 500 MB total · Output MP4 · Processed locally
Questions
Does Add Audio to Video upload my files?
No. The video and audio files are combined locally in your browser tab and are never uploaded to Utilumo.
Can I replace the original video audio?
Yes. Replace original audio is enabled by default, so the custom audio becomes the exported MP4 audio track.
Can I keep the original audio too?
Yes. Turn off Replace original audio to keep the existing audio as an additional track. Some players expose multiple tracks differently.
Does Utilumo upload my input?
No. Utilumo has no backend that could receive your input. Where a tool makes a request as part of its function, it goes directly from your browser to the destination you choose, never through Utilumo.
Do I need an account?
No. Utilumo tools are built to work without accounts or sign-in.