Age Calculator
Calculate exact chronological age from a date of birth to today or any as-of date, with years, months, days and total-day breakdowns.
Calculate age from date of birth
English age calculator intent is usually practical: enter a date of birth, choose an optional as-of date, and get chronological age in full years, months and days.
The subtraction is calendar-based, so full months and remaining days depend on actual month lengths.
What the result includes
- Exact age in years, months and days.
- Total days, weeks, hours and minutes as supporting date-duration values.
- Birthday countdown and progress through the current age year.
- February 29 birthdays use March 1 in non-leap years as this calculator's convention.
Frequently Asked Questions
Sources and References
- DateMDN Web Docs
- Representing dates and timesMDN Web Docs
- Gregorian calendarBritannica
- International System of Units: secondNIST
Calculations are based on the listed reference sources. Links open in a new tab.
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