Age Calculator
Calculate exact age between dates.
What this age calculator does
Calculate age between two dates, including years, months and days where supported by the calculator.
How to use the calculator
Enter the birth date and comparison date. The calculator accounts for calendar boundaries rather than simply dividing a number of days by 365.
How the calculation works
Age is determined from the calendar difference between the two dates. Because months have different lengths and leap years occur, calendar-based age is more precise for this purpose than a simple 365-day approximation.
What the result means
Example: if the birth date is January 1, 2000 and the as-of date is January 1, 2026, the exact age is 26 years, 0 months and 0 days.
Important assumptions and limitations
For legal eligibility or official documentation, use the date rules required by the relevant agency or jurisdiction. This tool is a general date calculation.
Frequently asked questions
The calculator compares the birth date with the selected as-of date and reports completed years, months and days using calendar dates.
Yes. Date arithmetic uses UTC calendar dates so leap days are treated as actual calendar days rather than as a fixed number of hours.
The calculator rejects that range because an age cannot be negative.
Yes. Enter a future as-of date to see the age that would be reached on that date.
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