M4A to MP3
Convert a voice memo or iTunes track for something that only plays MP3.
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or drag them here
M4A or AAC · as many as you like
- Takes
- M4A, AAC, and M4B (audiobook) files. Videos work too — MP4 and MOV — and only the sound is kept. Do several at once with the same settings.
- Size
- No limit. A two-hour audiobook is fine; a 12-minute file takes about five seconds.
Your files stay on your device
How to use it
Drop an M4A file here, like an iPhone voice memo, and pick a quality to get an MP3 for devices that won’t play M4A. Your file stays on your device.
iPhone voice memos and iTunes music come as M4A files. M4A actually sounds slightly better than MP3 — but some car stereos, DJ apps, dictation systems, and upload forms only accept MP3.
Drop your file onto the box above and pick a quality. Choose one close to the original (the tool shows it) — going higher won’t improve anything, it just makes the file bigger. Most voice memos are 64 kbps; music is usually around 256 kbps.
Converting loses a tiny bit of quality, since both formats are compressed. On speech you won’t notice. Keep the M4A if you might need it again.
FAQ
Will it lose quality?
A tiny bit, since M4A is already compressed. On voice memos you won’t hear it.
Should I pick a higher quality to be safe?
No. Higher can’t bring back lost detail — it just makes a bigger file. Match the original.
Will the file get smaller?
Usually not much, and it can get bigger. Convert for compatibility, not size.
Does it work with iPhone voice memos?
Yes, and they convert quickly. Leave mono on to keep them small.
Why does it say my browser can’t read the file?
Some versions of Firefox on Linux can’t read M4A. Chrome, Edge, or Safari will work.
How it worksFor the curious
An M4A is an MP4 container holding AAC audio. AAC is more efficient than MP3, so the same audio needs a slightly higher MP3 bitrate to hold up — converting rarely makes a file smaller.
The AAC is decoded with the browser’s built-in decoder and re-encoded as MP3 by a WebAssembly build of LAME. That is a second lossy generation; matching the source bitrate keeps the second pass from adding much damage, so the tool never preselects a bitrate above the source.
AAC decoding relies on codecs from your operating system. Chrome, Edge, and Safari always have it; some Firefox builds on Linux do not. The check runs against your actual file.