WMA to MP3 Converter
Convert WMA files (Windows Media Audio, Pro and Lossless) to MP3 in your browser. Choose the bitrate, keep tags, convert many files at once.
WMA (Windows Media Audio) was the default format of Windows Media Player and many CD rips from the 2000s. Phones, Macs, cars and most music apps do not play it, so this tool converts WMA to MP3 inside your browser, keeping the title, artist and album tags. It handles standard WMA, WMA Pro and WMA Lossless. Your files are not uploaded.
How to use this tool
- Choose one or more .wma files.
- Pick the MP3 quality: 192 kbps for music, 128 kbps for speech.
- Optionally switch to mono for voice recordings.
- Press Calculate and download the MP3s, one by one or as a ZIP.
Formula
MP3 size (bytes) ≈ bitrate (kbps) × 1000 ÷ 8 × length (s)
No browser can decode WMA, so the file is read by the ffmpeg engine (about 30 MB, downloaded once and cached) and encoded with LAME. Tags written by Windows Media Player (title, artist, album, year, genre, track) are carried into the MP3's ID3v2.3 tag. Files protected with Windows Media DRM cannot be decoded by any tool other than the licensed player.
Example
An album ripped as WMA at 128 kbps, 45 minutes long, is about 43 MB. Converted to MP3 at 192 kbps it becomes 192,000 ÷ 8 × 2,700 = 64.8 MB; keeping 128 kbps gives the same 43 MB.
Frequently asked questions
Which bitrate should I choose?
Match or exceed the WMA's own bitrate: converting cannot add quality back. 128 kbps WMA files are well served by 160–192 kbps MP3.
My WMA file will not convert. Why?
Most likely it is copy-protected (DRM), as files bought from old music stores often were. The error message says so when the engine detects it. Otherwise the file may be damaged.
Does it work on a Mac or phone?
Yes. The conversion runs in the browser, so you do not need Windows or Windows Media Player.
Last updated:
Page address with these inputs: https://kakao.mobile/tools/wma-to-mp3-tool/
Cite or embed this tool
kakaoCalc. (2026, November 8). WMA to MP3 Converter. https://kakao.mobile/tools/wma-to-mp3-tool/
“WMA to MP3 Converter.” kakaoCalc, 8 Nov. 2026, kakao.mobile/tools/wma-to-mp3-tool/.