Your age today is the time from your date of birth to now, counted as full years, then whole months, then the days left over, for example 31 years, 2 months, and 9 days. Enter your birth date in the calculator and you get that exact figure, plus your age as a total of days, weeks, or months.

People usually say their age in whole years, rounded down to the last birthday. The exact answer keeps the months and days too. It's counted on the real calendar, so leap years and the different month lengths are all included, the same way you'd track an anniversary, not by dividing days by 365.

The same count works for any date, not just today. Set the 'Calculate age at' field to a past day to find how old you were then, or a future day to see how old you'll be, handy for a birthday, a school cut-off, or an event you're planning around.