What happens when you convert WAV to M4A
- The audio is decoded and written as AAC at 192 kbps in an M4A container.
- WAV is lossless and M4A is not, so this is where size is saved: expect the M4A to be roughly one seventh of the size.
How to convert WAV to M4A online
- Press "Choose WAV 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 M4A". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
- Save each M4A with its download button. Close the tab and every trace of the files is gone from memory.
Why convert WAV to M4A?
WAV files usually come from recording, editing, sound effects and CD audio. People convert them to M4A because M4A is the native audio format of the iPhone, iTunes and Apple Music.
In short, WAV is good at what it was made for, and M4A is the more practical choice when the file has to play on another device or app. WAV plays in every browser and audio editor, while M4A plays in all current browsers and every Apple device.
How to convert WAV to M4A on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your WAV files in from File Explorer, and press Convert. Each M4A is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert WAV to M4A: choose Media, then Convert / Save.
On a Mac
Safari, Chrome and Firefox all work. Drag the WAV files from Finder onto the drop zone and the M4A files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose WAV files. You can pick from Photos or from the Files app. The converted M4A appears in Files, in the Downloads folder.
On Android
Open the page in Chrome, tap Choose WAV files and pick them from Files or your gallery. The M4A 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 WAV to M4A
M4A 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 |
Because the WAV is lossless, any bitrate you choose starts from a perfect source. 192 kbps is a safe default; go to 256 or 320 kbps if the music has a lot of cymbals, applause or reverb.
WAV vs M4A: the differences
| WAV | M4A | |
|---|---|---|
| Full name | Waveform Audio File Format | MPEG-4 Audio |
| Type | audio | audio |
| Created by | Microsoft and IBM | Apple, on the MPEG-4 standard |
| First released | 1991 | 2001 |
| Compression | Lossless | Lossy or lossless |
| Usually contains | uncompressed PCM, usually 16-bit at 44.1 or 48 kHz | AAC, or ALAC for lossless files |
| In a browser | plays in every browser and audio editor | plays in all current browsers and every Apple device |
| Common uses | recording, editing, sound effects and CD audio | iTunes purchases, iPhone voice memos and Apple Music downloads |
| MIME type | audio/wav | audio/mp4 |
About WAV and M4A files
What is a WAV file?
WAV normally stores raw, uncompressed samples: about 10 MB per minute of CD-quality stereo. Editors prefer it because nothing is lost between saves, and it is why a song is ten times larger than as MP3.
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.
WAV to M4A 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 M4A can store them, but cover art is not carried over.
Convert WAV to M4A 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 M4A with the same kind of settings:
ffmpeg -i input.wav -vn -c:a aac -b:a 192k output.m4aReplace input.wav with the name of your file. For a whole folder of WAV files, run the command in a loop, or drop them all on the converter above, which processes them one after another.
WAV to M4A converter FAQ
Will I lose quality converting WAV to M4A?
A little, because M4A is lossy. At the default setting the difference is hard to hear, and the file is much smaller.
Why is the M4A a different size from the WAV?
The M4A is usually far smaller, because lossy compression discards detail the WAV kept.
Are my WAV 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 WAV files to M4A 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 M4A file?
M4A plays in all current browsers and every Apple device. M4A is common for iTunes purchases, iPhone voice memos and Apple Music downloads.
Is this WAV to M4A 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 WAV to M4A 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.