This is a simple Bayesian probability calculator for the case of two dependent boolean variables, A and B. Fill in what you know, and other values will be computed whenever possible.

You can change the names of the variables:

variable = or , and

variable = or

Bayes' Theorem: $$ P(A|B) = {P(B|A) P(A) \over P(B)} $$

Things I should probably add: P(A and B), P(A or B), and explanatory text for people who aren't familiar with the notation or the concepts.