What is a WMA file?

WMA is a codec: the encoding itself rather than the box it travels in. It is used for handing a finished file over.

The extension is .wma, and the full name is Windows Media Audio. Both matter less than what the file can hold, which is what the rest of this page is about.

Microsoft published it in 1999.

A format that has been readable for that long is a format worth trusting with something you want back in ten years.

Reading it outside the vendor’s own software depends on work done by other people, usually by inspection rather than by documentation. That mostly works and occasionally does not, which is the reason to convert anything you intend to keep.

The people who made it have moved on, and support is being withdrawn rather than added. Anything still in this format is worth moving while the tools to move it are still around.

WMA discards detail to stay small, and what it discards does not come back. That is the right trade for something being looked at and the wrong one for something being edited: each re-save takes another bite.

Up to 8. Two covers stereo and is what almost everything is; more than two is surround, and it is the part most likely to be folded down when converting to a format that does not define it.

Windows Media Player and VLC read it, and so do most programs of the same kind.

If a file will not open, the format is rarely the problem — it is more often that the program predates it. Converting to something older is the reliable way past that, and it is what the rest of this site is for.

No browser reads it.

That is the single most common reason to convert it: not that the format is bad, but that the place you want to show the file cannot read it.

WMA is meant to be handed over rather than worked in. Editing one is possible and rarely pleasant; the sane approach is to change the source and export again.

The recurring complaints: support outside its home ground is uneven.

None of these is a reason to avoid the format. They are the things worth knowing before you are surprised by one, which is a different claim and a more useful one.

That is where nearly every WMA file comes from. Windows Media Player ripped to WMA by default for years, so anybody who put their CDs onto a computer between about 1999 and 2010 without changing a setting has a library of them — often the only copy, since the discs went to a charity shop long ago.

The rest come from the same era’s download stores, from Windows Mobile phones, and from voice recorders and dictation software that shipped with Windows. Almost nothing creates WMA now — FFmpeg still ships the `wmav1` and `wmav2` encoders, and little else does — which makes this a migration question rather than a format question.

WMA Standard is the ordinary lossy codec, the one a ripped CD is in. WMA Pro is a later, better lossy codec that far less software supports. WMA Lossless is genuinely lossless — bit-for-bit identical to the CD — and is the one worth identifying before converting anything. WMA Voice is a low-bitrate speech codec from dictation devices.

They all use the same extension, and the difference matters enormously at conversion time. Converting a lossless file to MP3 throws away real information; converting a lossy file to FLAC gains nothing and multiplies the size. A player showing file details, or a tool that reports the codec, will tell you which you have in a few seconds.

Music bought from the Windows Media era stores, and tracks from the subscription services of the time, were wrapped in DRM tied to a licence on a specific computer. Those licence servers are gone.

A protected file cannot be converted, and a converter handed one will report an error rather than producing audio. Files you ripped from your own CDs have no DRM and convert normally — which is the great majority of what people are holding. If a whole library refuses to convert, it was bought rather than ripped, and there is no supported route back.

Windows Media Player was retired, iTunes and the Apple ecosystem never played WMA, no browser supports it, no phone plays it natively, and most car systems and streaming devices refuse it. VLC and a handful of desktop players still do.

That is the practical case for migrating: not that the format is bad, but that the number of things able to play it shrinks every year while the number able to play MP3 or FLAC does not. A library nobody can listen to is not a library.

From WMA Lossless, convert to FLAC. Both are lossless, so nothing is given up, and FLAC is an open format supported by essentially every serious player. This is the one case where the conversion is genuinely free.

From WMA Standard, convert to MP3 or AAC at a high bitrate — 256 or 320. The source is already lossy, so this is a second lossy pass and there is no way around it; a high setting keeps the loss below what anyone will hear on ordinary equipment. Converting a lossy WMA to FLAC is the mistake to avoid: it produces a much larger file containing exactly the same degraded audio.

WMA files carry artist, album, track number, year and often album art, and a library of two thousand tracks that arrives with none of it is a weekend of work to repair.

Any decent conversion carries those fields across into the target format’s own tags. It is worth converting five albums, opening them in whatever player you use, and checking that the artist, album and track order came through before running the whole library — the alternative is discovering the problem at the end.

Work from the highest quality copy you have, which is the WMA rather than anything you already converted. Convert once rather than in stages, since every lossy step compounds. And keep the originals until the new library has been used for a while — disk is cheap and a re-rip is not possible for discs you no longer own.

If some of the CDs are still on a shelf, re-ripping those to FLAC is better than any conversion, because it starts from the disc rather than from a lossy copy of it. For the rest, a careful one-time conversion is the best that can be done, and it is worth doing before the next player drops support.