GMAT vs. other graduate school admissions exams

CPA is not really an entrace exam in the same way the MCAT, LSAT, GRE, GMAT are. The CPA is a killer, but it kind of is an end wthin itself. Once you have passed that exam, you're a CPA, rather than it gets you admitted to CPA school.

I think the MCAT is by far the hardest. It's so content based that you either know it or you don't. On the LSAT and GMAT, and parts of the GRE, you can figure out the answer by simple analytical thinking. On the MCAT, if you don't know the way electrons and protons behave with relation to each other, you're screwed.

The GMAT requires knowledge of math principles, and the LSAT requires deep logical thinking. They're similar in some of the verbal aspects, but with the Quant on the GMAT, you either know how to tackle the problem or you don't. You might be able to get the answer by shear force working through the problem, but that's going to take you way longer than you have time per question and will cost you in points when you have to guess at the end.

ranking the exams really is rather subjective. Someone that has been taking science classes for years and years will rock the MCAT because they know how that works. Put that same person in the seat of an LSAT exam and they'll freak. They'll think "Why do I care which horse comes in first in a race? Is one of them sick? Can I tell you about the way the horse's cell reacts to a disease? Please?"