Age Calculator

Our Age Calculator figures out the period or exact age between any two dates, presenting the result broken down into years, months, weeks, days, hours, minutes and seconds.

Different societies have their own ways of measuring age. Our tool follows the most widely used convention, where a person's age increments on their birthday. So someone who has been alive for 3 years and 11 months is considered 3 years old, turning 4 on the following birthday a month later. This is the standard approach in most Western nations.

Certain cultures count age either by including the ongoing year or not. Thus a twenty‑year‑old and someone who is in their twenty‑first year are regarded as the same age. In a traditional Chinese method, a child starts life at age 1 and gains a year at the Chinese New Year, not on their birthday. Consequently, a baby born a day before the New Year will be considered two years old just two days later, even though they are only two days old.

The month‑and‑day output of the calculator can be ambiguous when the start date falls on the month's last day. For instance, we treat February 20 to March 20 as a full month. Yet the interval from February 28 2022 to March 31 2022 can be handled in two ways: counting February 28 to March 28 as one month gives a result of one month and three days, while treating both dates as month‑end yields exactly one month. Both interpretations are valid, and similar edge cases appear with dates such as April 30 to May 31 or May 30 to June 30. The discrepancy arises from the varying lengths of months; our implementation follows the first approach.