Add audio to a video online — free
Add a music track or narration to a video. Upload your clip and an audio file, merge them, and choose whether to keep or replace the original sound.
How to add audio to a video
- Drop your video file into the upload box, or click to browse. Everything stays on your device.
- Upload your video and an audio track, then merge them together.
- Click Process — everything runs instantly in your browser, with nothing uploaded.
- Preview the result and download it — or send it straight to another JustGIF tool to keep editing.
Features
- Add music or narration to a video
- Keep or replace the existing audio
- Runs locally in your browser — your files never leave your device
- 100% free: no sign-up, no watermark, no file-count limit
- Works on any device — Windows, Mac, Linux, Android and iPhone
Frequently asked questions
Can I replace the original sound?
Yes — mute the original and add your new track.
Is Add Sound free to use?
Yes. Add Sound is completely free with no account, no watermark, and no limit on how many files you can process.
Do my files get uploaded to a server?
No. JustGIF processes everything locally in your browser, so your files stay private on your device and nothing is uploaded.
Does it work on my phone?
Yes — JustGIF runs in any modern browser, including Chrome and Safari on phones and tablets, with no app to install.