Free tool
M4A to MP3 converter
Drop an M4A file, such as an iPhone voice memo, to convert M4A to MP3 right here in your browser: pick the quality, and download the MP3 a few seconds later.
- Free
- Works on phones
- Nothing is uploaded
MP3 quality
Drop your M4A file here, or Choose your M4A file
Any audio or video file, up to 1 GB and 2 hours. It’s converted in your browser; nothing is uploaded.
MP3 encoding by LAME, open-source software.
Converting a voice memo? NoteOwl turns M4A recordings into transcripts with speaker names and notes, unlimited and privately on your Mac. Dictation into any app is free.
How it works
How do you convert M4A to MP3?
Choose the M4A file or drop it on the converter, and it converts at once: your browser decodes the AAC sound, and an MP3 encoder inside the page writes the MP3 at the quality you picked. Play it back, then download it.
- 1
Pick the quality
128 kbps is plenty for voice memos and talks; 192 or 320 kbps for music. Keep the original sample rate, or switch it off for 44.1 kHz.
- 2
Add the M4A file
Drop it on the box or choose it from your files. On an iPhone, pick it from the Files app. Nothing is uploaded.
- 3
Download the MP3
Play it back to check it, then download it. It keeps the M4A’s name, ending in .mp3.
What is an M4A file?
An M4A file is sound in an MPEG-4 container, almost always compressed with AAC. Apple devices use it everywhere: iPhone Voice Memos, QuickTime’s audio exports and many Mac apps save M4A, and so do Zoom’s audio-only recordings and Windows Sound Recorder.
- Voice Memos on iPhone, iPad and Mac
- What’s insideAAC sound; Apple Lossless when Audio Quality is set to Lossless in Voice Memos’ settings
- Zoom recordings saved to your computer
- What’s insideAn audio-only M4A file, saved beside the MP4 video
- Windows Sound Recorder
- What’s insideM4A with AAC sound, unless you choose another format
- QuickTime Player’s File → Export As → Audio Only
- What’s insideThe video’s sound as an AAC M4A file
| Where it comes from | What’s inside |
|---|---|
| Voice Memos on iPhone, iPad and Mac | AAC sound; Apple Lossless when Audio Quality is set to Lossless in Voice Memos’ settings |
| Zoom recordings saved to your computer | An audio-only M4A file, saved beside the MP4 video |
| Windows Sound Recorder | M4A with AAC sound, unless you choose another format |
| QuickTime Player’s File → Export As → Audio Only | The video’s sound as an AAC M4A file |
Why change an M4A file to MP3?
For compatibility. MP3 plays on practically everything: older car stereos and MP3 players, some Windows and Android apps, audio editors, and websites and forms that only accept .mp3 files. If your M4A already plays where you need it, there’s no need to convert it.
Is M4A better quality than MP3?
Usually a little, at the same bitrate: AAC is the newer, more efficient codec. Converting can’t add back detail the M4A left out, so choose a setting that fits what you’ll do with the file.
- 128 kbps
- File sizeAbout 1 MB a minute
- Good forVoice memos, lectures, calls and podcasts
- 192 kbps
- File sizeAbout 1.4 MB a minute
- Good forMusic; the converter’s default
- 320 kbps
- File sizeAbout 2.4 MB a minute
- Good forMusic you want as close to the original as MP3 gets
| MP3 quality | File size | Good for |
|---|---|---|
| 128 kbps | About 1 MB a minute | Voice memos, lectures, calls and podcasts |
| 192 kbps | About 1.4 MB a minute | Music; the converter’s default |
| 320 kbps | About 2.4 MB a minute | Music you want as close to the original as MP3 gets |
How do you get a voice memo off your iPhone?
Share it from Voice Memos and save it to the Files app, then pick it on this page in Safari. On a Mac, drag a memo from the Voice Memos list to the desktop to get its M4A file.
- 1
Save the memo to Files
In Voice Memos, tap the recording, tap the More button (•••), then Share, then Save to Files.
- 2
Open this page in Safari
Tap Choose file and pick the memo in the Files app. It converts straight away.
- 3
Download the MP3
Tap Download MP3. Safari saves it to the Downloads folder in Files, ready to share.
Can you turn an M4A recording into text instead?
Yes, on a Mac. NoteOwl imports M4A, MP3, WAV and MP4 recordings, transcribes them on your Mac with on-device AI models, labels each speaker and writes notes. For Apple’s own options, see how to turn a voice memo into text on a Mac.
FAQ
Questions about converting M4A to MP3
Is my M4A file uploaded anywhere?
No. NoteOwl’s M4A converter runs entirely in your browser: the file is read from your device, converted there by an MP3 encoder inside the page, and saved back to your device. Nothing is sent to NoteOwl or anyone else, and there is no account to create.
Can I convert an iPhone voice memo to MP3 on the iPhone itself?
Yes, in Safari. In Voice Memos, share the recording and choose Save to Files. Then open NoteOwl’s converter in Safari, tap Choose file and pick the memo. Safari saves the MP3 to the Downloads folder in the Files app.
Which MP3 quality should I choose?
128 kbps for speech, such as voice memos, lectures and calls: about 1 MB a minute. 192 kbps, the converter’s default, for music. 320 kbps is the highest MP3 allows, about 2.4 MB a minute. A higher setting can’t add detail the M4A didn’t have.
How long does it take to convert M4A to MP3?
A few seconds for most files: NoteOwl’s converter works many times faster than the recording plays. A 5-minute M4A converts to MP3 in about 2 seconds in Chrome on a Mac with Apple silicon, and an hour-long one in about 25 seconds.
What is the largest M4A file it can convert?
NoteOwl’s converter takes files up to 1 GB and 2 hours long in current Chrome, Edge and Safari. Two kinds of M4A are decoded whole, which limits them to 30 minutes: Apple Lossless voice memos, which only Safari can convert, and HE-AAC files in Safari. Older Safari versions take any M4A up to 30 minutes long.
Keep exploring
More free tools
- MP4 to MP3 converterTurn an MP4 video’s sound into an MP3 in your browser, Zoom and Teams recordings included; nothing is uploaded
- MOV to MP3 converterTurn a MOV video’s sound into an MP3 in your browser: iPhone videos, QuickTime and Mac screen recordings; nothing is uploaded
- WAV to MP3 converterConvert WAV to MP3 in your browser, 16-bit to 32-bit float at any sample rate, and see how much smaller the MP3 is; nothing is uploaded
- Audio to text converterTranscribe audio to text free: drop in an MP3, M4A, WAV or other recording and get an AI transcript with times, as text, SRT, VTT or Word; nothing is stored
- Online voice recorderRecord your voice in the browser with a level meter, timer and pause, play it back, and save it as MP3 or WAV; nothing is uploaded
Related
- Audio to textTranscription software for your Mac: drop in an audio or video file and get a speaker-labelled transcript with timestamps, unlimited, with nothing uploaded
- Voice memo to textHow to turn a Voice Memos recording into text on a Mac, with Apple’s own tools and with NoteOwl
- Voice notes on your MacVoice notes and dictations saved as searchable text on your Mac, with the raw words beside the polished version; free
- Audio trimmerTrim the start and end off a recording in your browser by dragging on its waveform; MP3, M4A, WAV and FLAC are cut without re-encoding
Recordings into notes, privately on your Mac
Free to download. Runs entirely on your Mac.
macOS 26 or later · Apple Silicon (M1 or newer) · 16 GB memory minimum, 24 GB recommended
About NoteOwl
NoteOwl is private AI meeting notes and memory for the Mac. It captures meetings without a bot joining the call, labels every speaker, writes summaries and action items, and builds a memory of every conversation that you can chat with — fully offline, because the speech recognition and the AI run on the Mac itself. Dictation into any app is free; Pro is a one-time purchase.
NoteOwl pricing: what’s free and what Pro adds
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