Convert WAV to ALAC

Before you start

ALAC, or Apple Lossless Audio Codec, is a lossless format. Converting a WAV file to ALAC does not reduce the audio quality, but the result will not be playable everywhere that accepts WAV. ALAC is generally most useful when you want smaller files than WAV while keeping lossless audio for Apple devices or applications that support it.

This process runs locally on your computer when you use an installed media converter. If you choose a web-based converter, the file is uploaded to that service, which affects how you should treat private or unpublished audio. Use the shortest practical path for the files you actually need to convert and avoid sending sensitive recordings to a service you do not trust.

Step-by-step instructions

The steps below use ffmpeg because it is available for macOS and Windows and can handle WAV to ALAC conversion directly. The exact command depends on the version you have installed, but the general syntax is the same.

Open a command prompt

On macOS, open Terminal. On Windows, open Command Prompt or PowerShell. If ffmpeg is not installed, install it through your package manager or from the official project website, and make sure it is available in the current session before continuing.

Run the conversion command

ffmpeg -i input.wav -c:a alac output.m4a

Replace input.wav with the actual WAV filename and output.m4a with the name you want for the ALAC file. The ALAC stream lives inside an M4A container, so the output extension is normally .m4a rather than .alac.

If the WAV file is in a different folder, either run the command from that folder or include the full path. Quote paths that contain spaces, for example on Windows:

ffmpeg -i "C:\Audio\input.wav" -c:a alac "C:\Audio\output.m4a"

Keep the original WAV file until the output has been checked. Conversion does not delete or overwrite the source file, and you can run the command again if you need a different filename or location.

Check the output

Play the resulting M4A file in an application that supports ALAC and listen for skips, silence or unexpectedly changed length. Since ALAC is lossless, the decoded audio should match the WAV source, but the file will not be byte-identical because it uses a different container and compression.

For a basic format and stream check, use ffmpeg to inspect the file:

ffmpeg -hide_banner -i output.m4a

Look for an audio stream showing alac as the codec, along with the expected sample rate and channel count. A short metadata warning is not itself a conversion problem, but a missing or truncated stream is.

Common problems and next steps

If ffmpeg reports that the alac encoder is unavailable, your build may not include it. Try a current build or use a media tool whose ALAC output is documented for your operating system. If the command completes but no file appears, check that the output path is writable and that you did not mistype the extension or filename.

If the M4A will not open in a particular app, the issue is usually container support rather than audio quality. In that case, confirm that the app supports M4A files containing ALAC, or test the file in another player before converting again.

For recordings with metadata such as track title or artist, add tags after conversion using a tag editor that supports M4A. Do not use file extensions or filenames alone as proof of the audio format; inspect the stream information when the format matters.