Days lived

What it's for

Years are a convenient and rather mute measure: saying «thirty-six years old» has no effect, saying thirteen thousand days does. It's the kind of number that goes on a birthday card, in a caption, in a presentation, or that you look at once in a while to realize how much time has really gone by. The page gives days, weeks and months all together.

How it's counted

Two calendar dates, the date of birth and today's, get compared, and the days in between are counted. Leap years are already in there, because nothing is multiplied by 365: what's read is the real calendar, in which 29 February either exists or doesn't.

The count is in whole days, not hours: what matters is the dates, not the time you open the page. That's a deliberate choice, because comparing an instant with a date leads to a one-day error depending on the hour and the time zone, and that's a defect deliberately removed here.

Months are an estimate, days aren't

Days and weeks are exact numbers. Months, on the other hand, come from dividing by 30.44, the average length of a month in the Gregorian calendar: it's the right measure for a sentence like «roughly four hundred months», but it doesn't match the months you'd count on a calendar one by one, because those run from 28 to 31 days. For an exact age in years, months and days you need a different calculation.

Nearby tools

For the exact age and the next birthday there is Age calculator; for the days between any two dates Difference between dates, and for how long until a date Countdown. If what you need is working days, which are a different thing, the page is Working days.