How tall will I be if I am 18 years old and my height is 5 and rsquo7 and my dad and height is 5 and rsquo8 and my moms height is 5 and rsquo5?

While genetics play a significant role in determining height, it's difficult to predict your final height with certainty. Based on your current height of 5'7" and your parents' heights, you may grow a little more, but you're likely close to your final height. Generally, sons can grow to be around the average height of their parents plus a few inches, so you might reach somewhere between 5'7" and 5'9". However, individual growth patterns vary widely.