How age is calculated
Count the full years since the birth date, then the full months since the last birthday, then the remaining days. Someone born on February 29 is usually treated as turning a year older on February 28 or March 1 in non-leap years, depending on the rule being used.
Frequently asked questions
Can I find my age on a past or future date?
Yes. Change the second date to any day to see how old someone was or will be on that date.
Why do some countries count age differently?
A few cultures traditionally counted a newborn as one year old. Most countries, including the United States, use the international method shown here.