Age Calculator

This calculator determines precise age by computing the interval between two dates using calendar-based arithmetic that respects actual calendar structure rather than simplified day-counting. The algorithm accounts for varying month lengths (28-31 days), leap years occurring every four years with century exceptions, and the exact day-month-year components to produce accurate results broken down into years, months, and days.

The calculation begins with year differences using integer subtraction, then applies month-offset logic to handle cases where the birth month hasn't yet occurred in the current year, requiring a year decrement. Day-level precision requires comparing specific day values and borrowing from the month component when the current day is earlier than the birth day, using the previous month's actual length. Leap year detection employs divisibility rules (divisible by 4, except centuries unless divisible by 400) for accurate February 29 handling.

Users can calculate exact ages for legal documents requiring official age verification, school enrollment eligibility checks, retirement planning, or milestone tracking. The tool additionally determines days until the next birthday, total days lived, weeks, hours, minutes, and seconds for detailed life statistics. All computations occur client-side using native JavaScript date functions and custom calendar arithmetic, ensuring instant results while maintaining complete privacy for sensitive birth date information.