Math

Probability Calculator

Calculate single event probability, multiple independent events, and conditional probability. Includes normal distribution lookup.

Using the Probability Calculator

Determine the likelihood of an outcome with our probability tool. Whether you are calculating the chance of independent events (AND) or mutually exclusive ones (OR), this tool provides both the decimal and percentage probability for any scenario.

How it Works

Enter the number of favorable outcomes.

Input the total number of possible outcomes.

Review the basic probability (P(A)).

Use the "Series" tab to calculate the probability of multiple sequential events.

Technical Formula


                        P(A) = favorable / possible

Favorable Outcomes

Total Outcomes