Age Calculator

Age calculation seems straightforward but involves interesting complexities when you consider calendar variations, time zones, and cultural differences. Our age calculator handles these nuances to give you accurate results whether you need your age for legal documents, medical records, or simple curiosity.

How Age Is Calculated

In most Western countries, age is calculated from the day after birth. When you are born, you are considered zero years old, and you turn one on your first birthday. This is called the Western age system or international age system. Our calculator uses this method, which is standard in the United States, United Kingdom, Canada, Australia, and most European countries.

Leap Years and Age Calculation

Leap years add an extra day (February 29) to the calendar every four years, with exceptions for certain century years. If you were born on February 29, you technically have a birthday only once every four years. In non-leap years, leap day babies typically celebrate on February 28 or March 1. Our calculator properly accounts for leap years when computing total days and exact age.

Cultural Differences in Age Counting

Different cultures count age differently. In the traditional East Asian age system, used historically in China, Korea, Japan, and Vietnam, babies are considered one year old at birth, and everyone gains a year on New Year's Day rather than their birthday. South Korea officially adopted the international age system in 2023. Our calculator uses the international system, but users from these regions should note their cultural age may differ.