Age Calculator
Find the exact age in years, months, and days between two dates.
Try an example
26y 10m 7d
Born on a Saturday
9,808
1,401 weeks
54 days
Falls on a Friday
About this calculator
What Is an Age Calculator?
An age calculator works out exactly how old someone is — or the exact time between any two dates — and shows it in years, months, weeks, days, hours and minutes. Enter a birth date and, optionally, a different end date, and you get a precise answer instead of counting on a calendar. It is useful for forms and eligibility checks, birthdays and milestones, anniversaries, and curiosity about how many days you have been alive.
How Age Is Counted
This calculator uses the most common system, the one used in most Western countries: your age goes up by one on each birthday. Someone who has lived 3 years and 11 months is 3, and turns 4 a month later. Other traditions count differently. In some East Asian systems a person is born at age 1 and gains a year at the New Year rather than on the birthday, so a baby born the day before the New Year can be "2" a couple of days later. The result you see here follows the birthday-based method.
Why Months and Days Can Look Odd
Months have different lengths, so the same pair of dates can be measured in more than one reasonable way. February 20 to March 20 is clearly one month. But from February 28 to March 31, you can say "one month and 3 days" (counting Feb 28 to Mar 28 as a month) or "one month" (treating both dates as month-ends). Both are defensible, which is why different tools sometimes give slightly different month-and-day breakdowns for dates near the end of a month.
What You Can Find Out
- Your exact age in years, months and days.
- The total number of weeks or days you have lived.
- The weekday you were born and how long until your next birthday.
- The time between any two dates, such as the length of a project or relationship.
Related Date Tools
To add or subtract days from a date, use the Date Calculator; for counting days between events, the Day Counter; and for expecting a baby, the Due Date Calculator.
Worked example
From a birth date of January 1, 2000 to a target date of June 15, 2025, the exact age is 25 years, 5 months, and 14 days.
Frequently asked questions
How is the age broken into years, months, and days?
It counts the number of full years first, then full months remaining, then whatever days are left over — the same way you'd count age by hand on a calendar.
Can I calculate age as of a date other than today?
Yes — the "as of" date defaults to today but can be set to any past or future date, useful for figuring out age at a specific event.
How does this handle leap years?
Calculations are based on actual calendar dates, so leap years (and February's 28 or 29 days) are accounted for automatically rather than assuming a fixed 365-day year.
What if the target date is before the birth date?
The calculator expects the "as of" date to be on or after the birth date — reverse them if you get an unexpected result.
