What happens when you convert M4A to MP3
- The audio is decoded and written as MP3 at 192 kbps.
- Going from one lossy format to another adds a small generation loss. Choose a bitrate at least as high as the source to keep it inaudible.
How to convert M4A to MP3 online
- Press "Choose M4A files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
- Adjust the settings if you need to: the bitrate controls quality and size. The defaults suit most people.
- Press "Convert to MP3". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
- Save each MP3 with its download button. Close the tab and every trace of the files is gone from memory.
Why convert M4A to MP3?
M4A files usually come from iTunes purchases, iPhone voice memos and Apple Music downloads. People convert them to MP3 because MP3 plays in every phone, car stereo, smart speaker and website, and it keeps music small.
In short, M4A is good at what it was made for, and MP3 is the more practical choice when the file has to play on another device or app. M4A plays in all current browsers and every Apple device, while MP3 plays in every browser, phone, car stereo and media player.
How to convert M4A to MP3 on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your M4A files in from File Explorer, and press Convert. Each MP3 is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert M4A to MP3: choose Media, then Convert / Save.
On a Mac
Safari, Chrome and Firefox all work. Drag the M4A files from Finder onto the drop zone and the MP3 files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose M4A files. You can pick from Photos or from the Files app. The converted MP3 appears in Files, in the Downloads folder.
On Android
Open the page in Chrome, tap Choose M4A files and pick them from Files or your gallery. The MP3 is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.
Best settings for M4A to MP3
MP3 is a lossy format, so the bitrate decides both the sound quality and the file size. Size grows in a straight line with bitrate: double the bitrate and the file doubles.
| Bitrate | Size per minute | Good for |
|---|---|---|
| 320 kbps | about 2.4 MB | the highest quality, for music you will keep |
| 256 kbps | about 1.9 MB | excellent music quality |
| 192 kbps | about 1.4 MB | the default: transparent for most listeners |
| 128 kbps | about 1.0 MB | good for music on the go and for podcasts |
| 96 kbps | about 0.7 MB | speech and audiobooks |
| 64 kbps | about 0.5 MB | voice notes and spoken word only |
The M4A was already compressed, so pick a bitrate at least as high as the original. Going higher does not add quality back, it only makes the file bigger.
M4A vs MP3: the differences
| M4A | MP3 | |
|---|---|---|
| Full name | MPEG-4 Audio | MPEG-1 Audio Layer III |
| Type | audio | audio |
| Created by | Apple, on the MPEG-4 standard | the Fraunhofer Institute |
| First released | 2001 | 1993 |
| Compression | Lossy or lossless | Lossy |
| Usually contains | AAC, or ALAC for lossless files | MP3 audio, typically 128 to 320 kbps |
| In a browser | plays in all current browsers and every Apple device | plays in every browser, phone, car stereo and media player |
| Common uses | iTunes purchases, iPhone voice memos and Apple Music downloads | music libraries, podcasts and anything that has to play everywhere |
| MIME type | audio/mp4 | audio/mpeg |
About M4A and MP3 files
What is an M4A file?
M4A is an MP4 file that only holds audio, which is why renaming one to .mp4 often works. Voice Memos on iPhone saves recordings as M4A.
What is an MP3 file?
MP3 is the most widely supported audio format there is, which is its whole appeal. At 320 kbps most listeners cannot tell it from the original; at 128 kbps cymbals and applause start to smear.
M4A to MP3 not working? Common problems
- The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
- The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
- Song titles are missing. Tags such as title and artist are copied when MP3 can store them, but cover art is not carried over.
Convert M4A to MP3 with ffmpeg
This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent MP3 with the same kind of settings:
ffmpeg -i input.m4a -vn -c:a libmp3lame -b:a 192k output.mp3Replace input.m4a with the name of your file. For a whole folder of M4A files, run the command in a loop, or drop them all on the converter above, which processes them one after another.
M4A to MP3 converter FAQ
Will I lose quality converting M4A to MP3?
A little. Both formats are lossy, so re-encoding compounds the loss slightly. Keep the default bitrate or higher and the difference is rarely noticeable.
Why is the MP3 a different size from the M4A?
It depends on the settings. At the defaults, the MP3 usually comes out close in size to the M4A; lower the bitrate for a smaller file.
Are my M4A files uploaded anywhere?
No. The conversion runs inside this browser tab using ffmpeg compiled to WebAssembly, so your files stay on your device. You can disconnect from the internet after the page and converter engine have loaded and it still works.
Can I convert several M4A files to MP3 at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open an MP3 file?
MP3 plays in every browser, phone, car stereo and media player. MP3 is common for music libraries, podcasts and anything that has to play everywhere.
Is this M4A to MP3 converter free?
Yes. There is no sign-up, no watermark and no limit on how many files you convert. The site is paid for by advertising, and because conversions run on your device there is no server cost per file.
Can I convert M4A to MP3 on my phone?
Yes. The converter works in Safari on iPhone and iPad and in Chrome on Android. Converted files are saved to the Downloads folder.