M4A to MP3
Convert M4A to MP3 online, free, in your browser — no upload, no install, no queue. Works with iPhone voice memos, iTunes rips and downloads. 128–320 kbps. No upload — runs 100% in your browser
or click to browse
How to use this tool
- Drop your .m4a file on the box above, or click to browse.
- Pick the MP3 bit rate — 128 kbps suits most music; 192+ for dense material.
- Your browser decodes the AAC audio and LAME encodes the MP3 on your device.
- Click Download. Nothing was uploaded at any point.
M4A to MP3: the honest version
An M4A file is AAC audio in an MP4 container — the default of Apple Music downloads, iPhone voice memos and most phone recordings. AAC is generally a touch more efficient than MP3 at the same bit rate, so converting M4A to MP3 is a sideways-or-slightly-down move. The reason to do it is compatibility: MP3 plays on car head units from 2008, ancient PA systems, dictation software and every device ever made, while M4A still trips up a stubborn tail of gadgets and apps.
Being lossy-to-lossy, the conversion compounds loss slightly. Keep the original M4A if you can; the MP3 is the travel copy. If the M4A is DRM-protected (music bought from the iTunes Store before 2009), no converter can legitimately decode it — this page reports the failure instead of producing a corrupt file.
Settings and sizes
128 kbps is the sensible default and gives about 0.92 MiB per minute of stereo audio. Voice memos convert beautifully at 128 kbps in mono (about 0.46 MiB per minute with 'Mix down to mono' ticked). Music you care about: 192–256 kbps. The format ceiling of 320 kbps buys little coming from a typical AAC source, but costs nothing but space if you want it.
Why the bit rate list starts at 128
Below 112 kbps stereo / 64 kbps mono, the LAME encoder quietly resamples your audio to a lower rate — you would receive a 24,000 Hz file from a 44,100 Hz request with no warning offered. Every option here is verified to sit above that threshold, so the file you download matches the settings you picked.
MP3 encoding on this page uses LAME (compiled to JavaScript as the lamejs library) under the GNU LGPL. Your audio never touches a server — only this page and the encoder library are fetched from the web.
Frequently Asked Questions
Is my M4A file uploaded to a server?
No. Your browser decodes the AAC audio itself and JavaScript on this page compresses it to MP3. Nothing leaves your device — load the page, disconnect the network, and it still works.
Will converting M4A to MP3 lose quality?
Slightly and permanently, as with any lossy-to-lossy conversion. At 128 kbps or above the difference from the M4A original is, for almost everyone and everything, unnoticeable — you are trading a sliver of fidelity for universal playback. The original file is never modified.
It says my M4A can't be decoded — what's wrong?
The two usual culprits: DRM protection (Apple Music purchases before 2009 were locked, and no legitimate tool will decode them) or a file renamed to .m4a that is actually video or something else. Voice memos, iTunes-ripped tracks and phone recordings convert without trouble.
Does this work with iPhone voice memos?
Yes — voice memos are plain AAC in an MPEG-4 container and decode in any current browser. Tick 'Mix down to mono' for roughly half the file size; speech does not miss the second channel.
Which bit rate should I pick?
128 kbps for music and voice memos alike; 192–256 kbps if you listen on decent equipment and the material is demanding. Lower rates than shown are not offered because the encoder would silently change your audio's sample rate down there.
Why is this free with no limits?
There is no server doing the work, so there is no per-conversion cost to pass on: your browser contains a full AAC decoder, and the LAME MP3 encoder is open-source software. The page just connects the two on your device.
Is converting M4A to MP3 legal?
For files you own and use yourself, yes, in general terms — and MP3's patents expired in 2017, so the encoding step carries no royalty. This page also satisfies the LAME library's LGPL condition of crediting the project, done in the note above.