AudioKit

MP3 to MP4 converter

Platforms like YouTube need a video, not an audio file. Add your cover art or a photo to an MP3 and get an MP4 ready to upload, in 16:9, square or 9:16.

  • Runs on your device
  • No upload
  • No sign-up
  • Free

1. Audio

MP3, WAV, M4A, FLAC…

Stays on this device: nothing is uploaded. You can also drag a file here or paste it.

2. Picture (optional)

Cover art or photo. Without one, the title is shown.

Stays on this device: nothing is uploaded. You can also drag a file here or paste it.

Shape

The picture is encoded at 1 frame per second, so even an hour-long track encodes quickly and stays small. Audio is AAC 192 kbps.

What’s inside the MP4

An MP4 is a box that can hold video and audio tracks (see how containers work). This tool fills it with two: your picture encoded as H.264 video at one frame per second, and your audio encoded as AAC. That combination plays on every phone, browser and social platform.

Going the other way? MP4 to MP3 pulls the audio back out, and MP4 to WAV gives you an editable uncompressed copy.

Questions people ask

How do I convert MP3 to MP4?

Choose the MP3, optionally add a picture (cover art, a photo or a logo), pick 16:9, square or vertical, and press Create MP4. AudioKit makes a video of your picture with your audio, in your browser, ready to upload.

Why can’t I just rename .mp3 to .mp4?

An MP4 is a video container, and YouTube, Instagram and TikTok reject MP4s without a video track. The converter adds that track: a still picture encoded with H.264.

Can I upload music to YouTube with this?

Yes. Use the 16:9 shape and your cover art. YouTube accepts the H.264 + AAC MP4 this produces. Only upload music you have the rights to; Content ID will flag copyrighted tracks.

Will the audio quality change?

The audio is re-encoded once to AAC at 192 kbps, the format MP4 players expect. That’s transparent for most listeners, and platforms re-encode uploads anyway.

Why is the video so small?

A still picture at 1 frame per second compresses to almost nothing, so the file is roughly the size of the audio. Platforms play it like any other video.

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