Age Calculator
Find your exact age, or the time between any two dates, in years, months and days. The calculator also shows the total days, hours and minutes and how many days are left until the next birthday. It works on calendar dates, so the answer is the same in every time zone.
How to use the Age Calculator
- Pick the date of birth. Under Age As Of, today's date is filled in. Change it to measure the age on another date.
- Press the Calculate Age button to see the age in years, months and days, the total days, hours and minutes and the days until the next birthday.
- To try other dates, change either date and press the button again.
How age is calculated
The calculator counts whole calendar months from the date of birth to the second date, then the days left over. Twelve months make a year. It does not divide days by 30 or 365. A month is complete each time the calendar reaches the day of the month you were born on. When a month has no such day, its last day stands in. The total days are the days from the birth date to the second date, and the hours and minutes are those days times 24 and 1,440. On the birthday itself, the next-birthday count runs to the following year's birthday, 365 or 366 days away.
Worked example
Someone born on 1990-03-15 measured on 2026-05-26 is 36 years, 2 months and 11 days old. That is 13,221 days in total, which the calculator also shows as 317,304 hours and 19,038,240 minutes. A month is complete each time the calendar reaches the day of the month you were born on. A month too short for that day ends on its last day, so someone born on January 31 is 1 month old on February 28, or February 29 in a leap year, and 1 month 1 day old on March 1. The days in the result count from the last completed month.
Frequently asked questions
How is age in months calculated?
Months are counted by elapsed calendar months from birth date, not by dividing days. Someone born March 15 turns one month old on April 15 regardless of how many days are in March.
Does the calculator account for leap years?
Yes. The calculator works in calendar dates, so February 29 counts as a day like any other. Someone born on February 29, 2000 turns a year older on February 28 in years without a February 29, so on February 28, 2001 they are 1 year, 0 months and 0 days old. In leap years the birthday is February 29 again. The next-birthday count runs to whichever of the two dates comes next.
Can I find the age difference between two people?
Enter the older person's birth date under Date of Birth and the younger person's under Age As Of. The calculator returns the difference in years, months and days.
How does the calculator get hours and minutes?
From the total days. It multiplies them by 24 for the hours and by 1,440 for the minutes. The form takes dates without a time of day, so the count runs from midnight to midnight.