That really depends on your CD you use. If you use it as data, it's measured in MB and then that will depend on the music file itself as all of them are different. I believe if you burn a regular CD that is not rewritable as a jukebox CD, the limit is 80 minutes. I haven't done that in so long that I can't guarantee that's the limit, but that's what I recall from memory. I've been making jukebox CDs from mp3 files which allows me the 700 MB function.