Age Calculator

Exact age in years, months, and days, plus totals in weeks, hours, minutes, and seconds.

Mathematically exact

Interactive calculator

This calculator becomes interactive when JavaScript is available. The page still provides its method, limits and related tools without JavaScript.

How it works

Age is calculated using calendar arithmetic: full years between the two dates, followed by the remaining months and then the remaining days. Example: born May 15, 1990, and measured on July 21, 2026, the result is 36 years, 2 months, and 6 days. If you were born on February 29, your calendar anniversary is treated as February 28 in non-leap years.

Result classification

Mathematically exact. The result uses deterministic calendar or arithmetic rules on the values you enter. Dates are normalized before calculation, and invalid inputs are rejected.

Limitations

Exact for the stated rule and valid inputs; it does not decide legal, medical, contractual or policy questions.

Frequently asked questions

Does this account for leap years?

Yes. Leap years are handled automatically throughout the calculation, including calendar age and elapsed-time totals.

What happens if I was born on February 29?

In non-leap years your calendar anniversary is treated as February 28, which is the common convention most registries and age calculators use.

Why do the total days/hours/minutes differ slightly from a quick mental estimate?

Those totals count the exact elapsed time, including extra days from leap years. A rough "years × 365" estimate will therefore differ slightly.

Practical guide

How to use the Age Calculator

Reviewed 27 July 2026
  1. Enter the known values.Use the date, time, place or duration requested above.
  2. Check the assumptions.Confirm time zone, weekend, inclusion and rounding choices when shown.
  3. Read and reuse the result.Copy, share or continue to a related tool without retyping unnecessary information.

Common uses

The Age Calculator is useful for birthdays, age eligibility checks, milestone planning and comparing ages.

Edge cases to check

Pay particular attention to February 29 birthdays, future comparison dates and different conventions for legal age.