Age Calculator

The age calculator works out exactly how old you are today. Enter your date of birth and it returns your age broken down into complete years, months, and days, along with the total number of days you have been alive and the weekday you were born on.

Most people know their age in years, but the finer breakdown is surprisingly useful. Forms and eligibility checks sometimes need an age in years and months; parents track a baby's age in months and days; and milestone birthdays are more fun when you can see the exact count down to the day. Because the calculator shows the total days too, you can spot round numbers like your 10,000th day.

The math looks simple but hides real edge cases, and this calculator handles them correctly. It uses actual month lengths, so the gap between, say, 31 January and 1 March is measured properly rather than assuming every month has 30 days. It accounts for leap years, so a 29 February birthday is treated exactly right. And it counts complete units only: you are 24 years old until the very day you turn 25, never rounded up early.

To use it, choose your date of birth and press Calculate age. Your age appears instantly below the form, with no page reload. A date of birth in the future is rejected with a clear message, since you cannot have a negative age.

All of the calculation runs privately in your browser — nothing about your date of birth is sent anywhere. If you need a related tool, the age difference calculator compares two people's ages, and the days between dates calculator counts the days between any two dates.

Age is measured by counting whole years from your date of birth up to today, then the remaining whole months, then the leftover days. Month and year steps use real calendar lengths and clamp at month ends, so leap days and month-end birthdays are handled correctly. The total-days figure is the plain day count between your date of birth and today.