mp3bat
MP4 → MP3

Private by design

Convert MP4 to MP3 without uploading a thing.

MP4 is the most common video format, and often all you want from it is the audio — a song, a lecture, a podcast. mp3bat extracts the audio track to MP3 right in your browser, no upload.

STAYS ON YOUR DEVICE
Drop an audio or video file, or click to choose
It opens here, in this tab — not on our servers.
WAV · M4A · AAC · OGG · FLAC · MP3 · MP4 · MOV · MKV · WEBM → MP3
✓ Your browser— — ✕ — —our servers
About MP4 → MP3. The audio track is extracted from the video entirely in your browser using the built-in engine. The first video conversion downloads the engine once (~32 MB), then it's cached — nothing is uploaded.

What is MP4?

MP4 (MPEG-4 Part 14) is the dominant container for video on phones, cameras, and the web, usually pairing H.264/H.265 video with AAC audio. Converting to MP3 keeps just the audio in a universally playable form.

How to convert MP4 to MP3

  1. Drop your MP4 file into the box above (or click to choose it).
  2. Pick a bitrate — 320 kbps for best quality, 192 kbps for a smaller file.
  3. Click Convert to MP3. It runs in this tab, on your device.
  4. Download your MP3. Nothing was ever uploaded.

FAQ

Does converting MP4 to MP3 upload my video?

No. The audio is extracted on your device with a WebAssembly build of ffmpeg. The video never leaves your browser — the first conversion just downloads the engine once.

Will the MP3 quality match the video's audio?

It's as good as the source audio allows. MP4 audio is usually AAC (already compressed), so pick 256–320 kbps to keep the extraction clean.

Is there a file size limit?

It runs on your device's memory, so very large videos use more RAM and take longer. For typical clips and songs it's quick.

Other conversions

New to this? See how the on-device conversion works, or the guide on choosing a bitrate.