Age Calculator

By calendar borrowing: full years are counted first, then whole months, then the remaining days — the same way you would count on a wall calendar. It is not total days divided by 30, which is only an approximation.

Leap-day birthdays are handled with the real calendar: in non-leap years the birthday is counted on February 28 for age purposes, and all day counts use actual month lengths.

Most disagreements come from the month-length shortcut: dividing total days by 30.44 gives an approximation. This calculator uses true calendar months, which is what people mean by years, months, and days.

No. The calculation runs entirely in your browser; your birth date never leaves the page and is not stored.

Complete days since your birth date, not counting today. Weeks, months, and hours are derived from the same calendar math.

Yes — enter any past date. It works for historical dates too, using the calendar your browser applies.