What is normal level of tsh and t4? what is more dangerous between the two?which indicates thyroid level?

TSH most sensitive: The TSH level is the more sensitive indicator of your thyroid function. The T4 level is useful if the TSH is abnormal. A normal TSH in most labs is between 0.4 and 4.5 miu/l, for total T4 it is between 4.5 and 12.5 mcg/dl.

They are: Evaluated together. When one goes up the other responds to go down in the normal state. Neither is "more " or less "dangerous". Units used are determined by the lab that performs the test.