Runs locally in your browser
Age Calculator
Calculate exact age in years, months, and days from a date of birth. See days lived and the next birthday, computed locally.
- Years
- 36
- Months
- 7
- Days
- 23
- Next birthday
- 2027-01-15
- Days lived
- 13384
Pick a birth date when you need civil age, not the span between two arbitrary project dates. Months and leftover days follow calendar rules.
Age is computed from today in this browser. The birth date is not sent to a server.
How to use
- Enter the date of birth.
- Read years, months, and leftover days.
- Note days lived and the next birthday date.
How it works
Years, months, and days borrow from the previous month when the day-of-month has not arrived yet. Next birthday rolls to next year if it already passed.
Days lived is the whole-day difference from birth to now. Time of day is not part of the civil tally.
Examples
Form age
A birth date of 12 March 1990 on 12 March 2026 shows exactly 36 years with zero leftover months.
Next party
If the birthday already passed this calendar year, the next date sits in the following year.
FAQ
Does it use the time of birth?
No. It uses calendar dates at the start of the day in the local zone.
Can I compare two dates that are not a birthday?
Use the date difference calculator for project spans.
How are leap days handled?
February 29 birthdays follow the local calendar when the current year has no 29th.
Is the birth date uploaded?
No. Age math stays in this browser tab.
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