Convert M4A to MP3
Drop an .m4a file and download an MP3 at 192 kbps. Sample rate and channel count carry through unchanged.
Most M4A files come from iPhone voice memos, Apple Music purchases, or a screen recorder’s audio track. All of them decode here as AAC and re-encode to MP3.
A second lossy pass
The AAC stream is decoded to PCM, then MP3 encodes that PCM with its own rules. Detail AAC removed is already gone, and MP3 removes a little more. Encoding at 192 kbps keeps the added damage small enough that it rarely matters for spoken word or casual listening.
Skip the round trip when you still have a WAV or FLAC master; encode that to MP3 directly.
Protected files
Anything carrying DRM, typically named .m4p, cannot be read. There is no decryption step in this pipeline, so the file fails at the probe stage rather than producing silent output.