keisoku

Parent and Child Age Calculator

Just enter the parent's and children's birth dates to instantly find the parent's age, each child's age, the parent-child age gap, and the parent's age at birth on any reference date. Add as many children as you like and compare the gaps between siblings in one table.

Input

YYYY/MM/DD

Children's dates of birth

YYYY/MM/DD

Result

Enter the parent's and children's dates of birth, plus a reference date.

How it works

  • Enter the parent's and children's dates of birth and a reference date (today by default) to see everyone's age, the age gaps, and how old the parent was when each child was born, all at once.
  • All ages are completed ages (the number of birthdays reached by the reference date). Change the reference date to the past or future to see the family's ages at that moment.
  • Tap "Add a child" to register any number of children and compare each child's age, age gap, and the parent's age at birth side by side in a table.
  • The age gap is the difference of completed ages on the same reference date, so it can appear to shift by one year depending on which birthday has already passed.
  • The parent's age at birth is the parent's completed age on the child's birthday. If a child's birth date falls before the parent's, it cannot be computed and is shown as "—".