Grow Youthful Biological Age Quiz Results. Your chronological age is 50 Your biological age is 42 Congratulations! The way that you are currently living your life should slow the rate at which your body is ageing. You should already look, feel and act younger than your chronological age You seem to be in good physical and mental health, feeling good about both yourself and your body. You should be able to live a fulfulling and independent life