MARRIAGE AT 20?!?!💍

I'm wondering what age is too young to be engaged/married. My boyfriends parents got married at 19 and 21 and my parents got married at 22 and 23, but for some reason I feel like they'd still be worried if we got married that young lol I don't know why. what do you guys think? Anyone get married in their early 20's???
EDIT: by 20, we'll have been dating 4 years