Age Calculator

Free Age Calculator

This free online age calculator works out your exact age from your date of birth — in years, months and days — and also shows your total months, weeks, days and hours lived, the day of the week you were born on, and a countdown to your next birthday. It’s completely free, needs no sign-up, and runs entirely in your browser, so your date of birth is private and never uploaded.

How to use the age calculator

1. Enter your date of birth in the first field.
2. Leave the second field as today, or change it to find your age on any past or future date.
3. Click Calculate age (it also updates automatically when you change a date).
4. Read your exact age in years, months and days, plus the totals and your next-birthday countdown.
5. Click Reset to start again with an empty form.

How is age calculated?

Your age is the time between your date of birth and a target date (today by default). The calculator first works out whole years, then months, then days using a borrow method. If the target day-of-month is earlier than your birth day-of-month, it borrows a full month: it adds the number of days in the previous month and subtracts one month. If the month count then goes negative, it borrows twelve months and subtracts one year. This is why the answer depends on the real length of each month.

Months are not all the same length, so February and leap years matter. A leap year adds February 29th, which changes how many days fall between two dates and can shift a person’s exact day count by one. Because this tool uses real calendar months and the actual days in each month, the result stays accurate across leap years and across months of 28, 29, 30 or 31 days. The totals (months, weeks, days and hours) are derived from the precise number of days between the two dates.

Frequently asked questions