Age Calculator

Enter your date of birth and read off your age in years, months, days, hours, and minutes — calculated to the moment you load the page. The calculator handles leap years and varying month lengths correctly, so February 29 birthdays don't drift.

For between-two-dates calculations (anniversaries, age at a specific event), set the comparison date to whatever you want — the difference computes the same way. Useful for figuring out exactly how old someone was on a particular day in the past, or how old they'll be on a future date.

The seconds counter ticks live, which makes the result feel viscerally accurate but doesn't change the underlying math. Days are the most useful unit for most practical purposes; minutes and seconds are mostly for novelty.

The arithmetic isn't hard but the calendar is. The calculator computes the integer year difference, then adjusts for whether the current date has reached the birth-month-and-day yet — if not, subtract a year. Same logic cascades down: integer month difference, adjusted for whether the day-of-month has reached. For exact day count, it converts both dates to a Julian day number (sequential count of days since a fixed reference) and subtracts. Julian day arithmetic sidesteps every leap-year and month-length edge case automatically.

Worked example: born March 15, 1990. Today (say, May 7, 2026): years = 2026 - 1990 = 36; the date in 2026 (May 7) is past March 15, so no adjustment — age 36 years exact. Months: from March 15, 2026 to May 7, 2026 is 1 month, 22 days. So total: 36 years, 1 month, 22 days. Now in days: from March 15, 1990 to May 7, 2026 is exactly 13,202 days (the calculator counts leap years correctly). At ~24 hours each, that's 316,848 hours — the kind of number that makes you reconsider how you spend a Tuesday afternoon.

Edge cases worth knowing: someone born February 29 has only one 'real' birthday every four years. Different jurisdictions handle this differently for legal age — most treat February 28 (or March 1 in some places) as the legal birthday in non-leap years. The calculator shows actual day count, which is unambiguous. Time zones can shift 'today' by a day on the boundary; the calculator uses your browser's local timezone, which usually matches your intent. For forensic precision (estate timing, legal age-of-consent in foreign jurisdictions), reach for a date library that handles timezone explicitly.