foobar2000 is a freeware audio player for Windows developed by Peter Pawlowski, a former freelance contractor for Nullsoft. It is known for its highly modular design and extensive SDK which allows third-party developers to do such things as completely replace the interface. Foobar2000 supports a large number of audio file formats, has many features for organising metadata, files and folders, and has a converter interface for use with command line encoders. To maximize audio fidelity in cases where resampling or downscaling in bit-depth is required, it provides noise shaping and dithering. There are a number of official and third-party components which add many additional features. The core is closed source, whereas the SDK is licensed under the BSD license.
Since version 0.9.5, foobar2000 supports Windows XP SP2/SP3 and later releases only. This version features a revamped default interface, with embedded support for album list, album art, spectrum visualization, and some other features and improvements.