Age calculator by date of birth to find exact age in years, months, weeks, and days, plus the precise time difference between any two dates.
Use this age calculator to find your exact age from your date of birth. Enter your birth date and a current or custom reference date to see your age in years, months, and days.
Because you can choose any reference date, it also works as an age calculator between two dates when you want to know exact age on a past or future day. This is useful for forms, school or work records, legal age checks, retirement planning, and milestone dates.
It also works as a how old am I calculator and gives a clear age difference between the birth date and the selected reference date, along with useful details such as your next birthday, total days lived, and other time totals in one result.
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Frequently asked questions about the age calculator
How do I calculate my exact age from my date of birth?
Enter your date of birth and use today or any other reference date. The calculator shows your exact age in years, months, and days.
Can I use this as an age calculator by date of birth?
Yes. This page is designed to calculate exact age directly from a date of birth and a current or custom reference date.
Can I use this as an age calculator between two dates?
Yes. Enter the birth date as the start date and any reference date as the end date, and the calculator will show the exact age difference between those two dates in years, months, and days.
Can I use this as a how old am I calculator?
Yes. It works as a quick how old am I calculator and also shows details like your next birthday and total time lived in other units.
Can I calculate a birth date from a known age?
Yes. In reverse mode, enter an age and a reference date to estimate the date of birth or the possible birth date range, depending on the unit you use.
Can I calculate the date when someone reaches a certain age?
Yes. Enter a date of birth and an age, and the calculator returns the calendar date when that age is reached.
