Free tool

Exact age calculator

Find out your exact age in years, months and days, how many hours you have lived, what day of the week you were born and when you will reach your next milestones, such as 10,000 days or a billion seconds.

Calculations run in your browser: we do not send or store the data you enter.

How exact age is calculated

Age in years, months and days is calculated by subtracting the date of birth from the reference date using the real calendar: full years are counted, then the full months since your last birthday and finally the remaining days. This is the method used in official documents and it differs from dividing days by 365, which gives small differences because of leap years.

The totals (days, weeks, hours, minutes and seconds) are obtained by counting the time elapsed between the start of the day you were born and the current moment in your time zone. They are approximate to the minute, because we do not know the exact time you were born.

What life milestones mean

Besides birthdays, there are other round numbers that are also worth celebrating:

10,000 days: reached at 27 years and about five months.
20,000 days: reached at 54 years and about nine months.
A billion seconds: equal to 31 years and about eight months.

Calculating these dates is a fun way to mark the passing of time with something different from traditional birthdays.

The day of the week you were born

Knowing the day of the week you were born is a classic of popular culture: according to an old English rhyme, Monday's child is fair of face, Tuesday's child is full of grace, and so on. It has no scientific basis, but it is a curious fact to share on your birthday.

Common uses of this calculator

Checking your exact age for paperwork or forms.
Finding out how many days are left until your next birthday.
Calculating someone else's age, or the age you will be on a future date, using the reference date field.
Finding out how many days of life you have lived, as a starting point for reflecting on how you use your time.

Frequently asked questions

Why does my age in days not match years × 365?

Because leap years add one day every four years. A 40-year-old has normally lived 10 more days than you get by multiplying 40 by 365.

Can I calculate age on a past or future date?

Yes. Fill in the "Calculate on date" field with the date you want, for example to find out how old you will be at a future event.

What if I was born on 29 February?

The calculator counts full years according to the calendar and, in non-leap years, shows your birthday on 1 March. This is the criterion applied by this tool; for official procedures, check the criterion used by each authority.

Is my data saved?

No. The calculation is done in your browser and the date you type is not sent to any server.