Age Calculator
How to Calculate Age from Date of Birth
Calculating your exact age means finding the difference between your date of birth and today's date. While it sounds simple, the varying number of days in each month (28, 29, 30, or 31) and leap years make manual calculation tricky.
This age calculator handles all of that automatically. Enter your birth month, day, and year, and you'll instantly see your age in years, months, and days — along with the day of the week you were born, your zodiac sign, and the number of days until your next birthday.
Age in Different Units
Besides years, months, and days, you may want to know your age expressed in other units:
- Age in months: multiply full years by 12 and add remaining months.
- Age in weeks: divide the total number of days you've been alive by 7.
- Age in days: count every day from your date of birth to today, including leap days.
The calculator above shows your age in years, months, and days. Use the nearby dates table (on specific date pages) to compare ages for dates around your birthday.
Frequently Asked Questions
How do you calculate age from date of birth?
How do you calculate age from date of birth?
To calculate your age, enter your birth month, day, and year in the calculator. It subtracts your date of birth from today's date, accounting for leap years and varying month lengths, to give your exact age in years, months, and days.
How to calculate age on a specific date?
How to calculate age on a specific date?
This calculator computes your age as of today's date. Simply enter the date of birth you want to check. For past dates, such as "how old was I on January 1, 2020", use the difference between the two dates in years, months, and days.
How is age difference calculated?
How is age difference calculated?
Age difference is determined by calculating the exact age for each person and then subtracting the smaller age from the larger. This calculator shows your exact age so you can compare it with another person's result.
What is the age calculation formula?
What is the age calculation formula?
The formula is: Age = Today's Date − Date of Birth. The calculator handles months of different lengths (28–31 days) and leap years automatically, ensuring an accurate result down to the day.
Popular Birth Dates
Related Birth Dates
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