Age Calculator
Enter your date of birth to find your exact age in years, months, days, and hours.
How to use the age calculator
The tool turns a date of birth into an exact age breakdown and a countdown to the next birthday. It handles leap years, variable month lengths, and Feb 29 birthdays correctly — so the result you get matches the legal/medical convention rather than a naive "days ÷ 365" approximation.
- Pick your date of birth using the date picker. The maximum allowed value is today — future dates are rejected.
- Read the age breakdown. Years, months, and days give you the calendar-accurate age (what you'd write on a form). Total days and total hours are useful for milestone counts like your 10,000th day.
- "Born On" shows the day of the week you were born. Good party trivia.
- Scroll to the Next Birthday block to see how many days remain and which weekday your birthday lands on this year.
The math
Years are counted by full trips around the sun. Months are the remaining full calendar months after that, and days are what's left. So someone born on March 15, 1990 and reading this on April 19, 2026 is 36 years, 1 month, and 4 days old — not "36.09 years" or any decimal approximation. Leap day babies get a March 1 fallback for the countdown during non-leap years, which matches the convention most legal systems use.
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