Hcg level 634 - where does that put a pregnancy?

Can tell: A single HCG level does not reliably predict gestational age. A normal pregnancy HCG will roughly double every 48 hours. Within the next several days the pregnancy should have grown enough to accurately date with ultrasound.

Early : First of all if its about you, congratulations! 634 is pretty early, the ranges of the weeks are somewhat wide so hard to tell you very specifically. It is just about 4-5 weeks.

Bloodtest not enough: The range of normal HCG levels in pregnancies vary dramatically. Your obgyn can perform an ultrasound in a week or two to establish your due date.