HexaConverter
m4amp3

Convert M4A to MP3

Free online converter for M4A files. The most widely compatible lossy audio format. Nothing to install, no watermark, and every file is deleted automatically.

Drag and drop your files

or

Upload a M4A file to convert it to MP3. Up to 3 files at once, 100 MB each.

Free · up to 3 files · 100 MB each · files deleted automatically after 1 hour.

About M4A and MP3

M4A .m4a

An MPEG-4 container holding audio only — usually AAC, sometimes lossless ALAC. The extension tells you the wrapper, not the contents.

Good for

  • Rich tagging, including chapters and artwork
  • Holds either lossy AAC or lossless ALAC
  • The standard for iTunes and Apple Music files

Trade-offs

  • The extension alone does not tell you the quality inside
  • Support outside Apple platforms is inconsistent

audio/mp4

MP3 .mp3

The format that made digital music portable. Lossy, thirty years old, and still the safest choice when you have no idea what will play the file.

Good for

  • Plays on essentially every device ever made
  • Small files at listenable quality
  • Patents long expired, so support is everywhere

Trade-offs

  • Lossy — detail is gone permanently
  • Beaten by AAC and Opus at the same bitrate
  • No transparency about what was discarded

audio/mpeg

M4A and MP3 side by side

M4A compared with MP3
M4AMP3
CompressionContainer — usually lossy AACLossy
Typically used forApple audio, audiobooks, podcastsMusic, podcasts, anything that must simply play

What changes when you convert M4A to MP3

This is a re-encode, not a repackage

Some tools can move a stream into a different container untouched when the codecs happen to line up. We do not — every job here is decoded and encoded again, so the conversion takes time in proportion to the length of the file and costs a small amount of quality even where a repackage would have been possible. In exchange the output is predictable: it plays everywhere, rather than inheriting whatever the source happened to contain.

What your MP3 will contain

The output is MP3 — written by LAME, the reference MP3 encoder, at 192 kbps by default. That sits comfortably above the point most people stop hearing a difference on ordinary equipment, and the bitrate is adjustable from 32 up to 320 if you want the file smaller or the quality nearer the source.

Re-encoding costs a little quality

Both formats are lossy, so this decodes M4A and compresses again as MP3. That second pass loses a small amount on top of what was already gone. It is barely audible once, and it accumulates if a file is converted repeatedly — so convert from the original rather than from a previous conversion.

Tags may not survive intact

M4A stores its metadata as MP4 atoms, and MP3 uses ID3. Standard fields such as title, artist and album normally map across. Anything without an equivalent on the other side — unusual custom fields, some ratings and play counts, occasionally embedded artwork — has nowhere to go. Check the tags before deleting the original if your library depends on them.

M4A to MP3 questions