tools.studio

M4A to MP3

Re-encodes the AAC inside your M4A to MP3 so it plays anywhere. Your file stays on your device.

Drop an M4A file here

Everything happens on your device — your files are never uploaded.

What this does

This tool decodes the AAC audio inside your M4A file and re-encodes it as an MP3. The decode runs through the browser's built-in WebCodecs; the encode runs through a LAME-based MP3 encoder loaded in the page, since browsers have no native MP3 encoder of their own.

Both AAC and MP3 are lossy, so this is a transcode, not a copy — the audio is decompressed and compressed again, which discards a small amount of detail. The result is a standalone .mp3 that plays anywhere MP3 is supported.

How it works

  1. 1 Drop your M4A file, or pick it from your device.
  2. 2 Click Convert to MP3 and watch the progress bar as it encodes.
  3. 3 Download your MP3. It never leaves your browser.

Built with open source

  • Mediabunny — Converts and edits video and audio in the browser via WebCodecs. Add-on encoders cover MP3, AAC, and FLAC. · MPL-2.0

Frequently asked

Does my M4A get uploaded to a server? +

No. The whole conversion runs in your browser with WebCodecs and an in-browser MP3 encoder. The audio never leaves your device, and there is no sign-up.

Will I lose quality converting M4A to MP3? +

M4A (AAC) and MP3 are both lossy, so re-encoding costs you a little quality. You usually can't hear it. Converting back to AAC later won't recover the detail this step drops.

Why does it take a few seconds? +

Browsers can't encode MP3 on their own. The tool decodes the AAC audio and re-encodes it with a LAME-based encoder. Bigger or longer files take a bit more time.

What happens to album art, titles, and other metadata? +

The conversion carries the audio stream across. Tags like title, artist, and embedded cover art aren't guaranteed to transfer, so treat the MP3 as audio only and re-tag it if you need that metadata.

Can I convert several M4A files at once? +

This page handles one file at a time. Convert one, download it, then drop the next. There's no hard file-size limit beyond what your device's memory can hold.

Does the converter keep stereo, sample rate, and length? +

Yes. The channel layout, sample rate, and full duration of the source carry through to the MP3. Only the codec changes from AAC to MP3.

Which browsers does it work in? +

Any current Chrome, Edge, Firefox, or Safari with WebCodecs support. It runs the same on Windows, macOS, Linux, and mobile — nothing to install.

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