How to Convert M4A to WAV

M4A files are compact and widely supported by phones and music players, but many audio editors, samplers, broadcast tools and older devices expect WAV. Converting M4A to WAV decodes the audio into uncompressed PCM, which makes it easy to edit and import almost anywhere. This guide shows three ways to do it on your own computer and explains how to confirm the result.

Before you start

An M4A file is an MPEG-4 audio container. It usually holds AAC audio, which is lossy, and sometimes ALAC, which is lossless. If a media info tool lists the codec as mp4a, that refers to AAC audio inside an MPEG-4 container, so an "mp4a to WAV" conversion follows the same steps as M4A to WAV.

• Work on a copy and keep the original file. The conversion is one-way in terms of metadata, so the original is your backup.
• Make sure the file is not copy-protected. Older iTunes Store purchases with the .m4p extension, or tracks marked as protected, cannot be converted by the tools below.
• Check free disk space. WAV is uncompressed: stereo audio at 44.1 kHz and 16-bit uses roughly 10 MB per minute, several times more than a typical M4A.
• Decide where processing happens. FFmpeg, Audacity and Apple Music convert files locally on your computer. Web converters upload your file to a server, so read the provider's own statement on storage and deletion before uploading private recordings or calls.

Find out whether the destination needs a specific sample rate or bit depth, for example 48 kHz for a video project or 16-bit 44.1 kHz for some hardware players. If there is no requirement, keep the source sample rate and channel count.

Step-by-step instructions

Option 1: FFmpeg (Windows, macOS, Linux)

FFmpeg is a free command-line tool. Install it using your system's usual method, then open a terminal in the folder that contains your M4A file. Replace input.m4a and output.wav with your own file names.

• Inspect the source: ffprobe input.m4a. Note the codec (aac or alac), sample rate, channels and duration.
• Run a basic conversion: ffmpeg -i input.m4a output.wav. This writes 16-bit PCM and keeps the original sample rate and channels.
• For a 24-bit ALAC source, or if you plan heavy editing, keep more precision: ffmpeg -i input.m4a -c:a pcm_s24le output.wav.
• If the destination needs a specific format, add options before the output name, for example -ar 48000 for 48 kHz or -ac 1 for mono.
• To convert every M4A in a folder on macOS or Linux: for f in *.m4a; do ffmpeg -i "$f" "${f%.m4a}.wav"; done
• If an output file already exists, FFmpeg asks before overwriting it. Answer no unless you intend to replace it.

Option 2: Audacity

• Open the M4A file with File > Open, or drag it into the Audacity window.
• If Audacity reports that the format is not supported, install the optional FFmpeg library and point Audacity to it in the Libraries section of Preferences, then open the file again.
• Avoid applying effects or changing the project rate unless you intend to alter the audio.
• Export the file. Recent versions use File > Export Audio, where you pick WAV as the format; older versions use File > Export > Export as WAV.
• Choose the encoding: Signed 16-bit PCM for general use, or Signed 24-bit PCM or 32-bit float if you will continue editing.
• Confirm or edit the metadata dialog if it appears, then save.

Option 3: Apple Music on Mac or iTunes on Windows

• Open the import settings: in Apple Music go to Music > Settings (Preferences on older macOS) > Files > Import Settings; in iTunes for Windows go to Edit > Preferences > General > Import Settings.
• Set Import Using to WAV Encoder and confirm.
• Select the track or tracks in your library.
• Choose File > Convert > Create WAV Version.
• The WAV copy appears in the library next to the original. Use Show in Finder or Show in Windows Explorer to locate the file. The original M4A is not changed.
• If you normally rip CDs with a different encoder, switch Import Using back afterwards.

Check the output

• Run ffprobe output.wav, or open the file properties, and confirm the codec is PCM (for example pcm_s16le or pcm_s24le) with the sample rate and channel count you expected.
• Compare the duration with the original. They should match closely.
• Listen to the beginning, middle and end, and check that both channels play and there is no distortion or unexpected silence.
• Expect the WAV to be much larger than the M4A. That is normal for uncompressed audio.

Keep these limitations in mind. Converting a lossy AAC file to WAV does not restore detail that was removed during the original encoding; it only stores the decoded audio in an uncompressed form. Standard WAV files are limited to about 4 GB, roughly six and a half hours of 44.1 kHz 16-bit stereo; for longer recordings FFmpeg can write the RF64 variant with the -rf64 auto option, but check that your destination software accepts it. WAV has limited tag support, so album art and some metadata may not carry over.

Common problems and next steps

• The file will not open or FFmpeg reports invalid data: the download may be incomplete, the file may be protected, or it may not really be M4A despite its extension. Check it with ffprobe and try a fresh copy.
• Audacity cannot import M4A: install the FFmpeg library and link it in Preferences, then restart Audacity if it still is not detected.
• Apple Music shows a different Create Version item: the menu names the encoder currently selected in Import Settings. Set it to WAV Encoder and the menu item changes.
• The destination rejects the WAV: it may require a particular format. Re-export with explicit settings, for example ffmpeg -i input.m4a -ar 44100 -c:a pcm_s16le output.wav.
• Audio plays at the wrong speed or pitch in an editor: the file's sample rate does not match the project. Convert to the project rate or let the editor resample on import.
• The audio is inside an MP4 video or an M4B audiobook: the same FFmpeg command works because it reads the container, not the extension. For video files add -vn to drop the picture.
• You only have an online converter available: use it for non-sensitive material and verify its file retention policy first.

Once the WAV checks out, keep the original M4A as your archive copy with its tags intact, and use the WAV for editing or import. If you later need to send the edited audio somewhere with size limits, export a compressed version from your edited WAV rather than from the original M4A.