Depends on the length of your upper and lower leg. Even then it's all subjective. I'm just shy of 6'2" and a 33" inseam but I ride a 172.5mm even though the "correct" size for me would be over 175mm. If you're new, you probably won't see too much difference and most bikes that would likely fit you at that height and inseam would come with a 172.5mm I'd imagine.