Conditional Probability
Enter three probabilities, validate their bounds, and calculate conditional probability without assuming independence.
A QUICK WALKTHROUGH
How to use this tool
- Enter P(A), P(B), and P(A∩B) as decimals from 0 to 1.
- Calculate to validate the probability bounds.
- Review P(A|B) and the displayed formula.
Probability bounds
Enter P(A), P(B), and P(A∩B). Values must obey probability bounds, and the conditioning event must have P(B) greater than zero.
Formula and assumptions
The result uses P(A|B) = P(A∩B) ÷ P(B). Independence is not assumed.
GOOD TO KNOW
Common questions
Does this calculator assume independent events?
No. It applies the conditional probability definition P(A|B) = P(A∩B) ÷ P(B), after checking valid bounds and P(B)>0.