How the age calculator works
Age is not just a subtraction of years. This calculator counts the exact calendar distance between two dates: full years first, then full months, then the remaining days — the same method used on official forms. When the day of the end date is smaller than the day you were born, it borrows the correct number of days from the previous month, which is why February and leap years are handled properly.
Age = years → months → days, borrowing days from the previous month when neededWorked example
Born on 15 March 2000, measured on 15 October 2026: that is 26 full years (to 15 March 2026), then 7 full months (to 15 October 2026), then 0 days — an exact age of 26 years, 7 months, 0 days, and 9,710 total days lived.
Age on a specific date
Change the second field to any date — a school cut-off, a job application's reference date, a retirement date — to find the exact age a person will be (or was) on that day. Forms that ask "age as of 1st September" need this, not a rough year subtraction.
Frequently asked questions
How old am I if I was born in 2000?
In 2026 you turn 26 — but your exact age depends on whether your birthday has passed yet this year. Enter your full date of birth above for the exact years, months and days.
What if I was born on 29 February?
On non-leap years most countries treat 1 March (some use 28 February) as the legal birthday. This calculator counts calendar time exactly, so your age in days is always correct; your 'birthday' in a non-leap year falls on the date your country uses.
Does the calculator count the day I was born?
Age is measured as completed time since birth, so the day you were born is day 0. The 'total days' figure is the number of full days between the two dates.
Why do some forms ask for age on a specific date?
Schools, sports leagues, licences and pensions set eligibility by your age on one fixed reference date, which can differ from your age today by almost a year.