The Drake equation is a formula used to estimate the number of detectable extraterrestrial civilizations in our galaxy. It was formulated by astrophysicist Frank Drake in 1961.
N = R x fp x ne x fl x fi x fc x L
The calculator allows you to estimate the number of alien civilizations in our galaxy that we may contact.
Some suggested starting numbers are given, but you can alter them and input your own figures if necessary.