Each person is classified yin or yang based on one of the five elements, depending on his or her year of birth. Learn your element here.
A person who is Metal or Water is yin.
A person who is Wood or Fire is yang.
Earth people can be either yin or yang since Earth goes between yin and yang. Consulting a Chinese almanac like 2011 Chinese Almanac by Peter So (ISBN 978-988-1905-6-9) or a fortune teller will help those who are Earth determine if they are yin or yang.
