I measured the bike from the ground to the top bar. 31". tires are 700x45 (not sure if that helps) I am 5'11". Unfortunately my legs are a little short...I wear a 30" inseam for pants. Being 74 of age, I have to be careful getting off the bike. It is just a little too tall for me. I would think the bike would be perfect for someone with an inseam of 32" to 36''. As to how tall, really don't know. Probably 5'7" is too small and 6'5" is too tall. But just guessing.Do you know size it is? How tall a person is it good for?