Calculate exact age

The age calculator works out exact age in years, months and days from a date of birth to a target date (today by default). Use it to verify age for school enrollment, insurance, visa applications, sports eligibility, or just to find out exactly how old you are in days. Calculations use the Gregorian calendar and handle leap years automatically.

How to use this calculator

1. Enter your date of birth.
2. Enter a target date (defaults to today).
3. The result shows your age in years, months and days, plus the total number of days and months you have been alive.

Worked example

Someone born on March 15, 1990 is, on July 7, 2026, exactly 36 years, 3 months and 22 days old — a total of 13,272 days. The calculator breaks that down into full years (36), full months after the last birthday (3), and remaining days (22), so the age reads naturally rather than as a single decimal number.

Frequently asked questions

How is exact age calculated?

Age is calculated as full years, then full months, then the remaining days between your date of birth and the target date. Leap years and months of different lengths are handled automatically using Gregorian calendar rules.

What target date does the calculator use?

By default the target date is today. You can change it to any date to calculate age as of a past or future point in time — useful for school enrollment cutoffs, insurance age, or age on a specific event date.

How does the calculator handle months with different lengths?

When the day of the month is greater than the number of days in the target month, the calculator uses the last valid day of that month. For example, born on the 31st of a month, the month-count rolls over correctly when the target month has only 28, 29 or 30 days.

Does the calculator account for leap years?

Yes. February 29 is handled correctly. Someone born on February 29 in a leap year is treated as having their birthday on February 28 in non-leap years for the purpose of the years/months/days breakdown, which is the standard convention.

Can I calculate age between two arbitrary dates?

Yes. Enter the earlier date as the date of birth and the later date as the target. The calculator works for any two dates, not just birth dates — useful for pet age, vehicle age, or time since any event.