M4A to MP3 converter
FileReshape's M4A to MP3 converter decodes the AAC or Apple Lossless sound in an M4A file and saves it as an MP3 at 128 to 320 kbit/s, using FFmpeg in your browser. The file is not uploaded. Title, artist and album tags are copied. Protected .m4p songs from the old iTunes Store and Audible audiobooks cannot be converted.
Did a file not convert correctly? E-mail [email protected], ideally with a small sample file, and it will be fixed.
Key facts
- Input: M4A (.m4a). Output: MP3 (.mp3).
- Your files are not uploaded: the work is done in your browser, on your own device.
- File size: up to 2 GB per file (the limit of the browser's WebAssembly memory).
- Needs a current browser (Chrome, Edge, Firefox or Safari) on a computer, tablet or phone; nothing to install.
- Free to use, with no sign-up.
M4A to MP3: why convert
An iPhone Voice Memo shared by AirDrop or email, a song from your iTunes library, an export from GarageBand or a recording from an Android recorder app is often an .m4a file. It plays fine on Apple devices, but a car stereo, an older MP3 player, a church or school sound system, a website builder or an upload form for a radio competition may only accept MP3. This converter reads the M4A in your browser, decodes its AAC sound (or Apple Lossless, if that is inside) and writes an MP3 with the LAME encoder at the bit rate you choose. Voice memos are usually mono, and the MP3 stays mono, so the file is small. Nothing is uploaded, which is a relief when the memo is a private conversation, a doctor's instruction or a meeting.
How to convert M4A to MP3
- Drop the M4A file in the box, or click to choose it.
- Check the sound details shown, and choose the MP3 quality.
- Click Convert to MP3 and save the MP3 file.
What changes when you convert
Two lossy steps
AAC in an M4A is already compressed with loss, and MP3 compresses again. Choose a bit rate at least as high as the original's: 192 kbit/s for an iTunes song bought at 256 kbit/s is fine for most ears, and 320 kbit/s keeps as much as MP3 can.
Protected .m4p files and audiobooks
Songs bought from the iTunes Store before 2009 have the extension .m4p and are encrypted, and so are Apple Music downloads and Audible .aa and .aax audiobooks. No honest converter can read them; the page tells you when a file cannot be decoded.
Voice memos from an iPhone
In the Voice Memos app, tap the recording, then the three dots and Share or Save to Files to get the .m4a file. Long memos of an hour or more work too; the conversion usually takes under a minute.
Cover pictures
Title, artist, album and track number are copied into the MP3's ID3 tags. The embedded cover picture is not copied; most music players add it again from the album information.
About the formats
M4A
M4A is an MPEG-4 file that holds only sound, usually compressed with AAC. It is what iPhone Voice Memos, Apple Music downloads without copy protection, GarageBand exports and many Android recorders save. AAC sounds a little better than MP3 at the same bit rate, but car stereos, old players, website builders and some upload forms still only take MP3.
- An M4A file is an MP4 file without a picture; the extension tells players to treat it as audio.
- Songs bought in the iTunes Store since 2009 are unprotected M4A files; older purchases are protected .m4p files.
- M4A can also hold Apple Lossless (ALAC), which keeps the sound exactly like FLAC.
- iPhone Voice Memos are mono AAC, typically 48,000 Hz and about 64 kbit/s.
MP3
MP3 is the most widely supported audio format. It was developed at the Fraunhofer Institute in Germany and standardised in 1993, and it plays on every phone, computer, car stereo and website. MP3 makes music about a tenth of its CD size by leaving out sounds people hardly hear.
- 128 kbit/s is fine for speech and podcasts; 192–320 kbit/s is used for music.
- The last MP3 patents expired in 2017, so the format is free to use everywhere.
- Title, artist, album and cover art are stored in ID3 tags at the start of the file.
- MP3 is lossy: every new encode loses a little more, so convert from the original when you can.
Frequently asked questions
Is my M4A file uploaded?
No. The conversion runs with FFmpeg inside your browser, on your own device. The memo or song never leaves your computer or phone.
Why is my file called .m4a and not .mp4?
They are the same file format. Apple uses .m4a for files that only hold sound, so that players treat them as music instead of video.
Does it work on an iPhone?
Yes, in Safari or Chrome. Choose the file from the Files app. On a phone the engine takes a moment to load, and very long recordings are slower than on a computer.
What about AAC files?
Plain .aac files, which some Android phones and recorders make, hold the same kind of sound and convert the same way. Choose them in the file dialog.