Does this age calculator upload dates?
No. The date calculation runs locally in your browser.
Age calculation runs locally in your browser. Nothing is uploaded.
Age Calculator
Choose a birth date and an optional as-of date to calculate calendar-correct age with years, months, days, total days, weeks, and months.
Age calculation runs locally in your browser. Nothing is uploaded.
Calculate age
Age result Choose a birth date to calculate age.
Calendar-correct age from two dates
Use this age calculator for birthdays, eligibility checks, records, forms, milestones, and date-based planning. It pairs naturally with the date difference calculator for general intervals.
The calculation borrows days and months from the calendar instead of using rough month lengths, so leap years and month boundaries are handled cleanly.
How to use this tool
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Enter a birth date
Choose the date of birth in the first date field.
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Set the as-of date
Use today's date or choose a different date for the age calculation.
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Copy the breakdown
Review years, months, days, total days, total weeks, and total months, then copy the result.
FAQ
Can I calculate age on a past or future date?
Yes. Change the as-of date to calculate age on any valid date after the birth date.
How are leap years handled?
The calculator uses actual calendar dates and month lengths, including leap-year February dates.
Why can total months differ from years times twelve plus days?
Total months counts complete calendar months in the age breakdown, while extra days remain separate.