Flac (; free lossless audio codec) is an audio coding format for lossless compression of digital audio, and is also the name of the reference codec implementation. digital audio compressed by flac's algorithm can typically be reduced to 50–60% of its original size and decompressed to an identical copy of the original audio data. flac is an open format with royalty-free licensing and a reference implementation which is free software. flac has support for metadata tagging, album cover art, and fast seeking. flac support in portable audio devices and dedicated audio systems is somewhat limited compared to lossy formats such as mp3 or uncompressed pcm, but flac is generally supported by more hardware devices than competing lossless compressed formats that may have intellectual property constraints.