How to convert WMA to MP3 on Mac (old Windows music, offline)

The music folder from an old Windows PC finally made it onto your Mac: a few thousand songs, sorted into artist and album folders, nearly all of them ending in .wma. For most of the 2000s, WMA was the format Windows Media Player ripped CDs into by default, so any collection built on a PC in that era is full of them. Drag the folder into the Music app and nothing gets added. Double-click a song and QuickTime Player refuses it. Press the spacebar in Finder and you get a blank preview instead of a play button.

The files aren’t damaged. Windows Media Audio is just a format Apple’s media stack has never read. The fix is to convert WMA to MP3 on your Mac once, and then the library plays everywhere. This guide covers the free Terminal route and the drag-a-folder route. Both run entirely on your Mac with nothing uploaded. It also covers the two checks worth doing before you start.

In this guide9 sections

Why your Mac won’t play WMA

WMA is Microsoft’s audio format from the Windows Media era. A .wma file is an ASF container, and the audio inside is one of four codecs:

WMA (sometimes labelled WMA Standard or WMA 9): the ordinary lossy format and the one almost every CD rip used, usually at 128 kbps.
WMA Pro: a higher-end lossy variant, sometimes multichannel.
WMA Lossless: a bit-for-bit copy of the CD, the Windows answer to FLAC and Apple Lossless.
WMA Voice: a low-bitrate speech codec used by some voice recorders and dictation software.

Apple never licensed or implemented any of them. QuickTime, the Music app and AVFoundation (the framework behind them) handle MP3, AAC, Apple Lossless, WAV and AIFF (QuickTime and Finder play FLAC too these days). None of them has ever handled ASF. Even afconvert, the audio converter built into macOS, doesn’t decode it. There used to be a workaround, the Flip4Mac plugin, but it was 32-bit and stopped working for good when macOS Catalina dropped 32-bit software in 2019. One more detail explains why these files keep turning up: iTunes for Windows could convert unprotected WMA files to AAC or MP3 as it imported them. The Mac version never could, so a library that moved from PC to Mac through iTunes often arrived half-converted.

If you only need to listen on this Mac, a free player solves it: VLC or IINA opens WMA directly. To get the songs into the Music app, onto an iPhone, into a car or into anything else built on Apple’s stack, you have to convert. WMA is the same dead end on a Mac as its video sibling, WMV, and the fix is the same: convert once.

Two checks before you convert

Is any of it DRM-protected?

Songs bought from Windows-era stores such as MSN Music, and tracks downloaded through subscription services like Zune Music Pass or Napster, were usually locked with Windows Media DRM. The audio in those files is encrypted, and no legitimate converter can decrypt it. The symptom is easy to spot: one set of files fails to convert in every tool while the rest of the folder goes through fine. If you still have the old PC, Windows Explorer shows Protected: Yes under a file’s Properties → Details. The real fixes are to re-rip the original CD, or to buy the track again from a store that sells unlocked files. CD rips made with Windows Media Player are normally unprotected unless someone turned on its “copy protect music” option, so most personal libraries convert without trouble.

Lossy or lossless?

It’s worth knowing which kind of WMA you have, because it decides the output. Plain WMA and WMA Pro are lossy, and MP3 or M4A is the natural destination. WMA Lossless is different: converting it to MP3 throws away the one thing that made it special. With ffmpeg installed (see below), ffprobe tells you in one line:

ffprobe -hide_banner "01 Track.wma"

Look at the Audio: line. wmav2 means ordinary WMA, wmapro means WMA Pro and wmalossless means lossless. Without Terminal, VLC shows the same thing under Window → Media Information → Codec Details.

MP3, M4A or FLAC?

MP3 plays on everything made in the last twenty-five years: old car stereos, cheap speakers, other people’s computers. Pick it when you don’t know where the files will end up.
M4A (AAC) is the more efficient choice if the library is going into the Music app and onto Apple devices. It sounds the same as MP3 at a smaller size.
FLAC is the right choice for WMA Lossless, because it’s lossless to lossless and nothing is thrown away. The Music app doesn’t import FLAC, so if the lossless files are headed there, convert the FLACs to Apple Lossless (ALAC) in a second pass. Lossless to lossless is still bit-perfect.

A note on bitrate. A 128 kbps WMA rip doesn’t gain detail when it becomes a 256 kbps MP3; the higher bitrate only makes sure the second encode doesn’t lose more. Lossy to lossy always adds a small generation loss, which is inaudible at sensible bitrates. So convert once, and keep the WMAs until you’ve listened to a few results.

Method 1: ffmpeg (free, command line)

The free tool that decodes all four WMA codecs is ffmpeg, installed with Homebrew:

brew install ffmpeg
ffmpeg -i "01 Track.wma" -c:a libmp3lame -q:a 2 "01 Track.mp3"

-c:a libmp3lame selects the MP3 encoder, and -q:a 2 is its high-quality variable-bitrate setting (about 190 kbps on typical music), which is plenty for a 128 kbps source. Use -q:a 0 if the WMAs were ripped at 192 kbps or higher. Titles, artists and album names in the WMA tags normally carry over into the MP3’s ID3 tags. For the other two destinations:

ffmpeg -i "01 Track.wma" -c:a aac -b:a 256k "01 Track.m4a"   # AAC for Apple devices
ffmpeg -i "01 Track.wma" -c:a flac "01 Track.flac"           # WMA Lossless only

If ffmpeg stops with a complaint about a video stream, that stream is embedded cover art. Add -vn to skip it.

Music libraries are nested (Artist/Album/Track), so a plain *.wma loop in one folder isn’t enough. This loop walks every subfolder:

cd ~/Music/"Old PC"
find . -name '*.wma' -print0 | while IFS= read -r -d '' f; do
  ffmpeg -nostdin -n -i "$f" -c:a libmp3lame -q:a 2 "${f%.*}.mp3"
done

-nostdin stops ffmpeg from swallowing the file list the loop is reading from (without it the loop can skip or mangle files), and -n stops it from overwriting an MP3 that already exists. The limitations: each MP3 lands next to its WMA, which means you’ll have to separate them again before importing, errors scroll past in a wall of output, and DRM-locked files fail with a decoder error that’s easy to miss.

Method 2: Zumkor (drag the folder, pick MP3)

If the WMAs are a whole library rather than a handful of files, this is the job Zumkor is built for. It needs macOS 14 or later on an Apple silicon Mac (M1 or later):

Open Zumkor and drag in the WMA files or the whole music folder. You can also select them in Finder and choose “Add to Zumkor” from the right-click Services menu.
Pick MP3. Zumkor turns WMA into MP3, M4A or FLAC, so pick M4A for an Apple-only library or FLAC for WMA Lossless.
Check a row. Every row shows the exact filename it will produce before anything converts.
Click Convert and choose where the new files go. Zumkor asks where to save, remembers the choice in Settings, and leaves the originals where they are.

There are no bitrate menus. MP3s are written at a high default (around 256 kbps), which is the right range for a lossy-to-lossy conversion. The details that matter at library scale:

A queue holds up to 2,000 files.
The list is still there the next time you open the app, even if the library sits on an external drive you unplugged in between.
Conversions keep running with the window closed.
Everything runs on your Mac. Nothing is uploaded, and converting works with Wi-Fi off, which matters for a private music collection.

If WMAs keep turning up from a family member’s PC, Zumkor’s “Convert Files” action in Apple’s Shortcuts app can run the same conversion from a folder automation without opening the app.

Pricing: everything is free for 7 days. After that you can keep converting 5 files a day (25 a week) for free, and audio is never watermarked (the small Zumkor mark goes on free videos only). A few thousand songs is a lot of days at that rate, which is what the Full Version is for: a one-time $19.99 purchase. Buy once and keep it forever. There’s no subscription and no account, and it’s shared with your family through Family Sharing.

If a few files and some Terminal work don’t bother you, ffmpeg is free and does the job. Zumkor makes sense when it’s a whole library, when you want the output in a clean folder of its own, and when the same old drive also turns up OGG downloads, FLAC albums and WMV home videos. It handles all of them.

Getting the converted songs into the Music app

Once the MP3s (or M4As) exist, the rest is drag and drop:

Import the output folder, not the old one. Drop the folder Zumkor wrote into the Music window, or use File → Import. If Copy files to Music Media folder when adding to library is turned on (Music → Settings → Files), Music keeps its own copies, so you can archive the loose files afterward.
Look at the tags first. Titles and artists usually survive the trip. Embedded album art is less reliable, because Windows Media Player often kept cover art as hidden files in the album folder rather than inside each song. If a few albums import without art, add it once in Music’s Get Info window.
Watch for duplicates. If an earlier PC-to-Mac move brought some of these songs over as AAC files already, you’ll get two copies of each. Music’s File → Library → Show Duplicate Items finds them.

Getting the conversion right

Don’t expect “better than the source.” No MP3 setting recovers what a 128 kbps WMA already threw away. The goal is to keep what’s there, and a high-bitrate MP3 does that.
Keep the WMAs until you’ve listened. Play a few converted tracks, including one quiet classical or acoustic track where artifacts show first, before you delete anything.
Voice recordings don’t need music settings. WMA Voice files from an old dictaphone are speech. MP3 is still the easy universal answer, and the files stay small. If a recording is mostly silence either side of the part you need, Zumkor’s trim (the QuickTime-style yellow handles, which work on audio too) converts only the kept range.
If the song is really inside a video, convert from the video instead. Zumkor can pull the audio out of an MP4 or MOV directly.

Bottom line

Just listening on this Mac: VLC or IINA plays WMA as it is. No conversion, but the files still won’t go into Music.
Comfortable in Terminal: brew install ffmpeg, then ffmpeg -i in.wma -c:a libmp3lame -q:a 2 out.mp3, looped with find for a nested library. Use -c:a flac for WMA Lossless.
A whole library, no scripts: Zumkor. Drag the folder, pick MP3, M4A or FLAC, and convert it all on your Mac into a folder you choose. Free for 7 days, then 5 files a day free, or a one-time $19.99 for everything.
Before any of it: set DRM-locked files aside, and send WMA Lossless to FLAC rather than MP3.

WMA support isn’t coming to the Mac, and the tools that once added it are gone. Convert the library once and it’s ordinary music again.

FAQ

Can a Mac play WMA files?

Not with Apple’s own apps. QuickTime Player, the Music app and Finder’s preview have never supported Windows Media Audio, and the old Flip4Mac plugin stopped working when macOS Catalina dropped 32-bit software. VLC and IINA play WMA fine, but to get the songs into the Music app or onto an iPhone you need to convert them to MP3 or M4A once.

Why won’t some of my WMA files convert?

Usually DRM. Songs bought from Windows-era stores such as MSN Music, or downloaded through a Zune or Napster subscription, were locked with Windows Media DRM, and the audio inside is encrypted. No legitimate converter can decrypt it. The fixes are re-ripping the original CD or buying the track again from a current store.

How do I convert a whole folder of WMA files to MP3 on a Mac?

In Terminal, install ffmpeg with Homebrew and loop it over the folder with find. Or drag the folder into Zumkor, pick MP3 and click Convert. Every file converts on your Mac with nothing uploaded, up to 2,000 files in a queue, and the MP3s go to a folder you choose while the WMA originals stay put.