Age Calculator

The calculator counts full calendar years from your date of birth, then full months, then the remaining days — the same way ages are counted legally. Because months have different lengths and leap years add a day, this calendar-based counting is more accurate than dividing the total days by 365.

Enter your date of birth and the "In total" panel shows your age as total months, weeks, days and hours lived. For example, a 25-year-old has lived a little over 9,130 days — the exact number depends on how many leap years the span includes.

Yes. The "Calculate age on" field defaults to today, but you can set any date — past or future. That answers questions like "how old was I on graduation day?" or "exactly how old will I be on 1 January 2030?".

Leap-day birthdays are handled the standard way: in non-leap years the birthday is counted on March 1, so the years figure only increases once the calendar passes the leap-day anniversary. Your totals in days and weeks are always exact regardless.

Completely. There is no sign-up and no cost, and the whole calculation runs locally in your browser with JavaScript — the dates you enter never leave your device, and the page keeps working offline once loaded.