Age calculator
Find your exact age in years, months, and days from your date of birth, on any date. See the day of the week you were born, your zodiac sign, and a countdown to your next birthday. Everything runs locally in your browser.
How to calculate your age
- Start with your date of birth and the date you want your age on. The calculator uses today by default.
- Count the whole years between the two dates. That is your age in years.
- Add the leftover whole months since your last birthday.
- Add the remaining days, borrowing from the previous month's length when needed. Leap years are handled automatically.
Example: from 5 December 2000 to 15 January 2021 is 20 years, 1 month, and 10 days. That is also about 241 months, or roughly 7,346 days. The calculator above shows the exact totals, the weekday you were born, your zodiac sign, and a countdown to your next birthday.
Age calculator FAQ
How do I calculate my age from my date of birth?
Count the full years from your birth date to today, then the leftover whole months, then the remaining days. For example, someone born on 5 December 2000, measured on 15 January 2021, is 20 years, 1 month, and 10 days old. This calculator does it instantly and also shows your age in total months, weeks, days, hours, and minutes.
How do I calculate age in Excel?
In Excel, put your date of birth in cell A1 and use =DATEDIF(A1, TODAY(), "Y") for full years, =DATEDIF(A1, TODAY(), "YM") for the leftover months, and =DATEDIF(A1, TODAY(), "MD") for the remaining days. This calculator gives the same result without a spreadsheet, and works for any date in the past or future.
What day of the week was I born on?
Enter your date of birth and the calculator shows the weekday you were born on, along with your age, your zodiac sign, and a countdown to your next birthday. It uses the Gregorian calendar and accounts for leap years.
How do I find my exact age on a specific past or future date?
Use the age at date field. Leave it blank to use today, or enter any past or future date to see how old you were or will be then. This answers questions like how old you were at an event, or how old you will be on a future date.
How is the age difference between two dates calculated?
The age difference tab takes any two dates and reports the gap in years, months, and days, plus totals in weeks, days, and hours. The order does not matter; it always shows the positive difference between the two dates.