Which plugin format should I use?

It depends on the Digital Audio Workstation (DAW) you own.

Here is a list of the most famous DAW compatible with each format :

  • VST (PC/Mac): 
    Cubase, Reaper, Ableton Live, Acid Pro, FL Studio, Sonar, Studio One, Nuendo, Samplitude

  • AU (Mac only):
    Logic Pro, Garage Band, Reaper, Ableton Live, Studio One, Digital Performer

  • RTAS (PC/Mac)
    ProTools (for version <= 10)

  • AAX (PC/Mac)
    ProTools (for version >= 10)