What audio format uses the least amount of memory mp3 wma wmv or wav?

WAV is normally used as an uncompressed audio storage format. It supports several formats but is most commonly used to store CD standard data, 44.1 kilobits per second on two channels. It will typically use about 10Mbyte per minute.

Both MP3 and WMV are compressed formats. They encode the data into smaller file sizes by losing some of the audio detail. There are many different compression ratiOS so in either case, the resulting data usage can be anywhere from 5Mbyte per minute down to Kbytes per minute. The smaller the file size, the lower the quality. A 128Kbit per second stream is usually considered to offer reasonable quality for music and at this size, music will use about 1Mbyte per minute.

As WMV and MP3 use similar techniques for compressing audio data, it is the compression settings that define how small the file will be rather than the choice of file format.