I'm looking at that difference, for me, right now (two adjacent desks). It's about 15 1/4 inches (39 cm). P.S. When sitting, I have my desk 1 - 1 1/2 inches

I'm looking at that difference, for me, right now (two adjacent desks). It's about 15 1/4 inches (39 cm). P.S. When sitting, I have my desk 1 - 1 1/2 inches lower than "typical", primarily to provide a better typing position.