Age Calculator
Enter your birth date and an as-of date to calculate age using calendar arithmetic.
A QUICK WALKTHROUGH
How to use this tool
- Enter a valid birth date and as-of date.
- Calculate the age.
- Review the calendar age and next birthday.
Calendar age
Age is calculated in completed years, months, and days from the supplied dates. The birth date cannot be after the as-of date.
Local calendar dates
Dates are interpreted as calendar dates in your local time zone and processed locally in your browser.
GOOD TO KNOW
Common questions
Are invalid dates rejected?
Yes. Dates such as April 31 are rejected, and the birth date must not be later than the as-of date.
What happens on February 29?
A leap-day birthday uses February 28 in a non-leap year for the next-birthday display.
Is my birth date uploaded?
No. The calculation stays in your browser.