Depends how they measure it. Some manufacturers measure compact frames on the actual seat tube length (which could be center of bottom bracket-to-center or top/seat tube junction, center-to-top of seat tube, or center-to-top edge of top tube), and others give a virtual seat tube measurement (how long the seat tube would be if it intersected with a horizontal top tube).
I'd pay more attention to the virtual top tube length (length that the top tube would be if it were horizontal). For me, that's always been far more important. The compact frames I've felt most comfortable on are those where the virtual top tube length is about the same as the top tube length I ride on a traditional geometry frame.
__________________
