Age Calculator
Find your exact age in years, months, and days, plus the day of the week you were born.
Runs in your browser — nothing is sent or saved.
How to work out your age
- Pick your date of birth.
- Leave the second date as today, or set it to any date you want.
- Your age shows in years, months, and days.
- You also see the day you were born and how long until your next birthday.
How the age is counted
The tool counts full calendar months and days, the way people do. If you were born on the 15th, you gain a month on the 15th of each month, not after a flat 30 days. It also handles leap years, so a birthday on 29 February is counted correctly against years that have no 29th. This is why the day count can shift a little from month to month.
More than one age
Age can be shown different ways, so the tool gives a few. The main line is years, months, and days. Below it you see your age in total days and in total months, which is handy for a baby's age or a form that asks for months. The next-birthday line counts down the days.
Why the "as of" date helps
You can set the second date to the past or the future. Set it to a job start date to find your age on that day, or to a future date to see how old you will be at an event. Change either date and every number updates at once.
Leap years and different age systems
The calculator counts full calendar months and days, and it handles leap years, so a birthday on 29 February is counted correctly in years that have no 29th. Not every culture counts age the same way. The system used here is the common one, where you are 0 at birth and gain a year on each birthday. In one traditional East Asian system, a person is 1 at birth and everyone adds a year at the new year rather than on their own birthday, so the two systems can differ by a year or two.
FAQ
Does it count leap years?
Yes. Leap days are included, so ages that cross 29 February are counted correctly.
Why do the days change from month to month?
Months have different lengths. Because the tool counts real calendar months, the leftover days shift depending on which months you cross.
Can I find my age on a past or future date?
Yes. Change the second date to any day. The result shows your age on that date.
What if I was born on 29 February?
The tool handles it. In years without a 29th, it counts the birthday at the end of February.
Is my birth date sent anywhere?
No. The date stays in your browser and nothing is saved.
How do I see how old am I today?
Type your date of birth and leave the second date as today. You get your exact age in years, months, and days, and the total row shows your age in days as one number.
How old will I be on a future date?
Yes. Set the second date to the future day, like an exam or visa date, and the result is your age on that day.