M4A to MP3 Converter
Convert M4A/AAC audio to MP3 in your browser at 128–320 kbps. Free, private, no signup — nothing is uploaded to a server.
About the M4A to MP3 Converter
This free M4A to MP3 converter turns Apple/AAC .m4a audio files (voice memos, downloaded music, podcast clips) into universally-compatible MP3s. You pick the quality — from a compact 128 kbps up to a near-transparent 320 kbps — and get an instant player plus a download.
Everything runs inside your browser using FFmpeg compiled to WebAssembly, so your audio is never uploaded to a server. The conversion engine (about 30 MB) downloads from a CDN the first time you use any converter on the site and is then reused, which is why the very first conversion takes longer than the rest.
A couple of honest notes: MP3 is a lossy format, so re-encoding will not add quality that was not in the M4A — choose a higher bitrate to preserve more detail. Files up to 100 MB are supported; larger files are better trimmed first, since all the work happens in your device's memory.
How to Use the M4A to MP3 Converter
- 1Choose an M4A (or AAC) file, up to 100 MB.
- 2Pick the MP3 bitrate — 192 kbps is a good default, 320 kbps for best quality.
- 3Click Convert to MP3 and wait for the progress bar (the first run also downloads the converter).
- 4Play the result to check it, then download your MP3.
Frequently Asked Questions
Is my audio uploaded to a server?
No. The conversion happens entirely in your browser with FFmpeg WebAssembly. Your file never leaves your device — only the converter engine is downloaded, once.
Why is the first conversion slow?
The first time you use any converter here, the browser downloads the FFmpeg core (about 30 MB) from a CDN and compiles it. After that it stays cached in memory, so later conversions are much faster.
Which bitrate should I choose?
128 kbps gives small files fine for speech and casual listening. 192 kbps is a balanced default. 256–320 kbps keeps the most detail for music, at a larger file size.
Will converting improve the audio quality?
No — MP3 is lossy, so converting can only preserve or reduce quality, never add it. Pick a higher bitrate if you want to keep as much of the original as possible.
Is there a file size limit?
Yes, 100 MB per file. Because processing runs in your browser's memory, very large files can be slow or run out of memory. Trim long recordings first if needed.