Add Audio

Add an audio track to a video file. Replace or overlay the existing audio.

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Free — no sign up, no watermark

How to Use Add Audio

  1. Upload the video file in the first slot — MP4, MKV, MOV, etc.
  2. Upload the audio file in the second slot — MP3, WAV, AAC, FLAC, or OGG
  3. Enable 'Loop Video to Match Audio' if the audio is longer than the video and you want the video to repeat
  4. Click Process to merge the audio into the video and download the result

Features

  • Add any audio file to a video as the soundtrack
  • Output as MP4, MKV, or MOV
  • Option to loop the video to match the full audio length
  • 100% private — files never leave your browser

Frequently Asked Questions

Does this replace the original audio?
Yes, the new audio file replaces the existing soundtrack entirely. To keep the original audio and mix in additional audio, use our Mix Audio tool instead.
What if the audio and video are different lengths?
By default the output length matches the shorter track. If your audio is a full song and the video is shorter, enable 'Loop Video to Match Audio' to repeat the video until the song ends.
Can I add a voiceover to a video?
Yes. Record your voiceover as an MP3 or WAV, upload it as the audio file, and the tool will replace the video's soundtrack with your recording.