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Age Calculator

Free age calculator: enter your date of birth to find your exact age in years, months, and days, plus total days lived and the weekday you were born on.

About this tool

Knowing your exact age down to the month and day is useful more often than you might think - for official forms, birthday planning, retirement math, or just curiosity. Doing the subtraction by hand is surprisingly easy to get wrong, especially across leap years.

Our age calculator gives you an exact answer in seconds. Enter your date of birth and it tells you your age in years, months, and days, plus the total number of days you have lived and the day of the week you were born on.

How to use

Pick your date of birth from the calendar field and press Calculate Age. That is all there is to it.

The result shows three things: your precise age (for example, 27 years, 4 months, 12 days), the total days you have been alive, and the weekday of your birth. It is a fun detail to share at birthday parties - most people have no idea which day of the week they were born.

The math behind it

The calculator subtracts your birth date from today's date. It first finds the difference in years, then adjusts the months and days so the result is exact - borrowing days from the previous month when needed, just like you would on paper.

Leap years are handled automatically because the math uses real calendar dates. The total-days figure is simply the number of 24-hour periods between the two dates, and the weekday comes from the calendar itself.

Frequently asked questions

Why is my age in months and days useful?
Some official forms, insurance quotes, and medical records ask for age with extra precision. Parents also like tracking a baby's age in months. And for retirement or pension math, knowing exactly where you stand helps you plan the remaining time more accurately.
Does the calculator handle leap years?
Yes. Because it works with real calendar dates rather than assuming every year has 365 days, leap years are counted correctly. Someone born on February 29 still gets an exact age - the calculator treats March 1 as their birthday in non-leap years, the common convention.
Can I calculate an age between two past dates?
Yes - the same math works for any two dates. Our days-between-dates tool is built for exactly that kind of span, while this calculator is optimized for the classic 'how old am I today' question.

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