The PM123 supports:

- Playlist support, including Playlist Manager and Shuffle support. Also supports WarpAmp (.LST), WinAmp (.PLS), Internet (.M3U) and Unicode (.M3U8) style playlists.
- Drag and Drop support.
- Skin support, including WinAmp skin converter.
- Plug-in supports:
  - Visual - See what you hear.
  - Decoder - Play anything.
  - Filter - Make it sound better.
  - Output - Play it or Save it anywhere.
- The usual Fast Forward, Rewind and Seek Slider.
- An Tags Editor.
- Possible to setup as a Netscape Navigator and Mozilla helper application to use with mpg123 and Ogg Vorbis HTTP Streaming.
- Remote Control through Pipes.
- Bookmark System.
- And a whole lot of other widgets...

Included plug-ins have the following features:

- mpg123 - Decoder for MPEG Audio Files.
  - MMX support.
  - 10 band ISO R10 standard serie Graphic Equalizer.
  - HTTP and FTP Streaming support including SHOUTcast and icecast.
  - Also supports Title Streaming.
  - Can save streaming data to hard disk.
  - The usual Fast Forward, Rewind and Seek Slider.
- oggplay - Decoder for Ogg Vorbis Audio Files.
  - HTTP and FTP Streaming support including SHOUTcast and icecast.
  - Also supports Title Streaming.
  - The usual Fast Forward, Rewind and Seek Slider.
- wavplay - Decoder for WAV files.
  - HTTP and FTP Streaming support.
  - The usual Fast Forward, Rewind and Seek Slider.
  - Also decode AIFF (Apple/SGI), AU (Sun/NeXT), CAF (Apple Core Audio File), IFF (Amiga IFF/SVX8/SV16), MAT4 (GNU Octave 2.0 / Matlab 4.2), MAT5 (GNU Octave 2.1 / Matlab 5.0), PAF (Ensoniq PARIS), PVF (Portable Voice Format), SD2 (Sound Designer II), SDS (Midi Sample Dump Standard), SF (Berkeley/IRCAM/CARL), VOC (Creative Labs), W64 (SoundFoundry WAVE 64), XI (FastTracker 2).
- cddaplay - Play CD tracks through CDDA.
  - Playing through CDDA allows filtering of the music.
  - FreeDB support.
  - The usual Fast Forward, Rewind and Seek Slider.
- analyzer - A Spectrum Analyzer and Oscillscope.
  - Uses Fast DIVE API.
  - Real-Time analysis and display of currently playing data.
  - Fallout Rate, Update Frequency and Percentage of viewed spectrum can be changed.
- os2audio - Outputs sound to your sound card.
  - Uses Fast DART API.
  - Conversion of 16 bit streams to 8 bit for 8 bit sound cards.
  - Millisecond accurate fetching of data for Visual Plug-ins.
  - Dynamic Priority Boost.
  - Support for Shared and Multiple sound cards.
  - User changeable amount of buffered decoded data for a more responsive system.
- wavout - Outputs sound to your hard disk.
  - Outputs sound directly to your hard disk in WAV format.
- realeq - A Professional Equalizer for music lovers.
  - MMX optimization to allow unprecedent amount of coeficient. Up to 4096 on a Celeron 500.
  - 32 1/3 octave ISO R10 Standard Serie bands.
  - Independant control of the Left and Right channel.