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MP3 to MP4

Turn an MP3 into an MP4 video with a picture or a plain background, ready for YouTube. Processing stays on your device.

Files stay on your device

Drop an MP3

Then add a picture or pick a color, and save a video that plays it. Nothing is uploaded.

MP3, M4A, WAV, FLAC, and other audio, or a video with sound.

How to convert MP3 to MP4 online

Open an MP3, add a cover image or pick a background color, and save an MP4 that plays the song over it. The MP3 to MP4 converter runs in your browser on Windows, Mac, or a phone, with nothing to install and no upload.

  1. Step 1

    Choose your MP3
    Pick a file or drop it into the converter above.
  2. Step 2

    Add a picture
    Add an image or pick a background color.
  3. Step 3

    Download the MP4
    Save the video when it finishes.

What to expect

Supported inputs
MP3 files, and any other audio or video with sound this browser can read. Pictures can be PNG, JPEG, or WebP.
What happens
The sound plays over a still picture for its full length. MP3 audio is encoded as AAC (MP3 where the browser has no AAC encoder); AAC audio is copied as it is.
Limits
One sound file at a time. The picture stays the same for the whole video; use Add audio to video to put a song under moving footage.

Private by design

Your video stays on your device

Mastershot processes your file locally in this browser. It does not need to be uploaded to a server, and you do not need an account to use the tool.

  • No upload
  • No signup
  • No watermark

Questions