M4A is the sound-only MP4 file Apple uses everywhere: songs from iTunes and the Music app, iPhone voice memos, GarageBand exports, and audiobooks (as .m4b). Most phones and computers play it, but plenty of things do not: older car stereos, USB sticks in a hi-fi, some MP3 players, dictation and transcription services, and websites that only take MP3. Converting to MP3 makes the file play on all of them.
This page converts with FFmpeg, the open-source media library, built for this site; its source is published at /source/ffmpeg/. It is free to use, with no account and no upload limit, and it runs entirely in your browser: nothing is uploaded, and while the page stays open, a feature you have already used keeps working offline.
- Does converting M4A to MP3 lose quality?
- A little, as any change between two compressed formats does: the AAC sound is decoded and compressed again as MP3. At 192 kbps or more most people cannot hear the difference from a typical 256 kbps iTunes song. Picking 320 kbps does not get back detail the M4A did not have; it only makes a bigger file. An Apple Lossless M4A is the best starting point, since nothing was thrown away before.
- How do I convert an iPhone voice memo to MP3?
- Voice Memos saves .m4a files. In the Voice Memos app, tap the recording, tap the three dots, then Share, and choose Save to Files. Then open this page in Safari, tap the box and pick the memo from Files. On a Mac, drag the memo out of the Voice Memos app onto this page. Choose 128 kbps: speech does not need more, and the file stays small enough to email.
- Are the song details and album art kept?
- Yes. The tags FFmpeg reads from the M4A (title, artist, album, year, track, genre, comment) are written to the MP3 as ID3v2.3, the version Windows, macOS, iTunes and most car stereos read, and a JPEG cover, the kind iTunes and most taggers store, is copied into the MP3 unchanged (a PNG cover is left out).
- Can it convert songs bought from iTunes?
- Songs bought since 2009 are unprotected .m4a files and convert like any other. Older purchases with the .m4p extension are locked to the Apple account that bought them, and no converter can read them. Apple Music downloads are protected the same way.
- Is there a size or number limit?
- There is no set limit. Files are converted one at a time in your browser, so a long audiobook takes a while and needs free memory; a phone may struggle with files of several hundred megabytes, where a computer copes.
- Are my songs and voice memos uploaded?
- No. The conversion runs in your browser on this device and the files are never sent anywhere, which matters for private recordings such as voice memos, interviews and meetings.