Age Calculator This will display your age along with the day you were born. Just enter the birthday you wish to track and the application will display the person's age, down to the second (assuming you were born at midnight exactly). Birthday: January February March April May June July August September October November December 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31