Age Calculator

It's calculation of a person's age can vary across different cultures. This calculator is based on the most commonly used age system. In this system, a person’s age increases on their birthday. For example, a person who has lived for 3 years and 11 months is considered 3 years old, and their age will increase to 4 on their next birthday, one month later. Most Western countries follow this age system.

In some cultures, age is expressed by counting years either including or excluding the current year. For example, a person who is twenty years old is considered the same age as someone in their twenty-first year of life. In one traditional Chinese age system, people are considered 1 year old at birth, and their age increases on the Traditional Chinese New Year instead of their birthday. For instance, if a baby is born just one day before the Traditional Chinese New Year, they will be considered 2 years old two days later, even though they are only 2 days old.

In certain cases, the month and day results from this age calculator may be confusing, especially when the starting date falls at the end of a month. For example, we consider February 20 to March 20 as one month. However, there are two ways to calculate the age from February 28, 2022, to March 31, 2022. If we count from February 28 to March 28 as one month, the result is one month and 3 days. If we treat both February 28 and March 31 as month-ends, the result is one month. Both methods are valid. Similar situations occur with dates like April 30 to May 31, May 30 to June 30, etc. This confusion arises from the uneven number of days in different months. In our calculations, we use the first method.

Key Notes:

• Cultural Variations: Western vs. East Asian age-counting traditions.
• Month-End Ambiguity: Explains why dates like Feb 28–Mar 31 can yield different results.
• Calculator Methodology: Uses the "same day next month" approach (e.g., Feb 28 → Mar 28 = 1 month).