How to Calculate Age
What is Age?
An age calculator determines exactly how long a person has been alive, broken down into years, months, and days. It accounts for varying month lengths and leap years to give a precise age.
Step-by-Step Guide
- 1Subtract birth year from current year for base age
- 2Adjust if birthday has not yet occurred this year
- 3Break down remaining difference into months and days
Worked Examples
Input
Born: Jan 15, 1990 → Today: Apr 1, 2025
Result
35 years, 2 months, 17 days
Input
Born: Feb 29, 2000 (leap day) → Apr 1, 2025
Result
25 years, 1 month, 1 day
Feb 29 birthdays count as Feb 28 in non-leap years
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