How it works
The calculation subtracts completed years, then completed months, then remaining days. Leap years are included in the date difference.
Productivity / HXD Labs
Age calculator
Enter a birth date and a reference date to calculate age by completed birthdays.
Result
Fill in the fields to see the result.
How to use
Age uses completed calendar years and months. Total days are counted between the selected dates; the next birthday is shown separately.
Example
Someone born on March 15, 2000 turns 26 on March 15, 2026; on March 14 they are still 25.
Good to know
For a February 29 birth date, this tool treats March 1 as the birthday in non-leap years. Legal rules may use another convention.