Home › Guides › How to Calculate Your Exact Age in Years, Months and Days

How to Calculate Your Exact Age in Years, Months and Days

Work out your exact age for forms and eligibility checks, by tool or by hand.

By the ToolWorlds team · Updated 2026-10-29

Why exact age matters

Admission forms, job and exam notices, insurance and visa applications often ask for age in years, months and days. Being off by even a day can change whether you are eligible.

Using the calculator

Open the Age Calculator.
Choose your date of birth.
Read your exact age, the number of days you have lived and the days left until your next birthday.

Calculating by hand

Subtract your birth year from the current year. If your birthday has not happened yet this year, subtract one. For months, count full months since your last birthday. For days, count from the same day number in the previous month. If the current day number is smaller than your birth day number, borrow the days of the previous month, just like subtraction on paper.

Age on a cut-off date

Many notices ask for age on a fixed date, such as the last date to apply. The calculator always uses today, so for a fixed date count the years, months and days between your birth date and that date, and read the notice carefully for how it counts.

Leap day birthdays

People born on 29 February celebrate on 28 February or 1 March in other years, and the legal rule varies by country. The next-birthday countdown here treats it as 1 March.

Try it now: Age Calculator – Find your exact age in years, months and days, and days to your next birthday.