How to Convert WMA to M4A

Apple never licensed the WMA codec for their devices or software. iOS, macOS, iTunes, and the Music app have no native WMA decoder. When you try to open a WMA file on an iPhone or drag one into iTunes, you get an error. This is a longstanding incompatibility that Apple has never addressed — their preference is AAC (delivered in M4A containers), which they developed as part of the MPEG-4 standard. M4A is the correct target format for any audio you want to play natively on Apple hardware. Every iPhone back to the first generation, every iPad, every Mac with OS X 10.3 or later plays M4A/AAC natively.

Standard WMA is a lossy format. Converting WMA to M4A is a transcode — the audio is decoded from WMA and re-encoded as AAC. This introduces a second generation of lossy compression. Quality loss is real but often minimal at decent bitrates. If your WMA files are 192 kbps or higher, converting to 192 kbps or 256 kbps M4A will produce files that sound essentially identical to the original. If your WMA files are 128 kbps, match the output bitrate (128 kbps M4A) to minimize additional quality loss — going higher won't help because the original data is already compressed. For the best possible outcome, go back to the CD source and rip fresh as AAC or FLAC rather than transcoding WMA.

Open AudioUtils in any browser on your computer. Upload your WMA file by dragging it to the converter. Select M4A as the output format. Choose your bitrate based on the source: match the source WMA bitrate or go one step higher. Common choices: 128 kbps for spoken word WMA files, 192 kbps for music at medium quality, 256 kbps for music you care about preserving well. Click convert and download the M4A file. The output .m4a file can be dragged directly into the macOS Music app or iTunes on Windows. For batch conversions of a large WMA library, upgrade to AudioUtils Pro and process files one by one — the converter handles each file fully in your browser, so your audio never leaves your device.

With iTunes open on your Windows or Mac machine, drag the converted M4A files into the iTunes window. iTunes will add them to your library and sync them to any connected iPhone on next backup. Alternatively, File > Import on iTunes browses for files. If you are on macOS Catalina or later, iTunes has been replaced by the Music app — the import process is identical. On iPhone, you can also add M4A files directly via the Files app if they're in a supported location, and play them with the native Files app music player or import to Music via AirDrop from a Mac.

WMA files purchased from old Microsoft Music or other early digital music stores may contain DRM (Digital Rights Management) protection. These files are licensed to specific devices and cannot be converted directly — the DRM prevents access to the audio data. AudioUtils and most conversion tools cannot decode DRM-protected WMA files. To convert these files, you typically need to play them through the licensed Windows Media Player and use a real-time audio capture method. Alternatively, if you purchased the music legitimately, many artists and labels have made their catalogs available on streaming platforms or new DRM-free stores. Checking if your purchased tracks are available on Bandcamp, iTunes Store, or Amazon Music as DRM-free re-downloads is often the easiest path forward.