Probability Calculator
Calculate simple probability from favorable and total equally likely outcomes.
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How to use this tool
Enter the number of favorable outcomes and total equally likely outcomes, then calculate.
Important to know
Calculate simple probability from favorable and total equally likely outcomes.
This assumes outcomes are equally likely. It does not model dependent events, weighted outcomes or real-world uncertainty.
Formula and methodology
P(event) = favorable outcomes ÷ total outcomes; complement = 1 − P(event).
Example
For one favorable outcome among six equally likely outcomes, probability is about 0.166667, or 16.67%.
Frequently asked questions
Can favorable outcomes exceed total outcomes?
No. Favorable outcomes must be between zero and the total number of outcomes.