What is the Bayes Theorem Calculator?

The Bayes Theorem Calculator is a simple tool that helps users determine the updated probability of an event after receiving new information. By entering the prior probability of A, the likelihood of B occurring when A is true, and the likelihood of B when A is false, the calculator applies Bayes’ Theorem to compute P(A|B). This allows students, teachers, and researchers to understand how evidence changes the probability of an event, making it useful in statistics, decision-making, diagnostics, machine learning, and real-world prediction scenarios.

How to Use:

1. Enter P(A): Provide the initial or prior probability of event A (between 0 and 1).
2. Enter P(B|A): Input the probability that event B happens when A is true.
3. Enter P(B|¬A): Enter the probability that B happens when A is not true.
4. Click “Calculate”: The calculator applies Bayes’ Theorem to find P(A|B).
5. Review Result: The output displays all entered probabilities, the computed posterior probability P(A|B), and a short explanation to help interpret the result.