How to use the age calculator
Enter your date of birth in the first field and your exact age appears instantly — broken down into years, months, and days, along with the total number of months, weeks, and days you have lived, and how many days remain until your next birthday. To find your age on a date other than today (for example, on the day of an exam or the start of a school year), fill in the optional second field.
How age is calculated
The calculator uses the calendar method: it first counts the number of complete years since your birth, then the number of complete months after that, and finally the remaining days. Because calendar months have different lengths (28 to 31 days), this is the only method that matches how birthdays actually fall — a person born on 31 January turns one month old on the last day of February, not on a fictional "31 February".
Total days are counted as the exact number of calendar days between the two dates, which also accounts for leap years automatically. Total weeks are total days divided by seven, rounded down.
Common uses
People use an age calculator for more than curiosity: filling in official forms that require age in completed years, checking age eligibility for school enrolment, sports leagues, or retirement benefits, calculating an infant's age in weeks or months for medical checkups, and finding out the exact day of the week they were born.