Calculate single and compound event probabilities, percentage chances, and fractional odds.
Result
Calculated using classical Laplace probability theory.
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P(A) = Favorable Outcomes / Total Outcomes | P(A') = 1 - P(A)
Rolling an even number on a 6-sided die: 3 favorable out of 6 total.
Probability: 50.00% (1 in 2 chance | Odds: 1 : 1).
Calculate the number of unordered combinations (nCr) of selecting r items from n choices.
Open calculatorFind the number of ordered arrangements (permutations) of r elements from n total items.
Open calculatorCalculate percentage of a value, percentage change, and ratio percentage instantly.
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Open calculatorNo. Probability is bounded strictly between 0 (impossible event) and 1 (certain event).
The complement of event A is the probability that A does NOT happen, calculated as P(not A) = 1 - P(A).
Classical probability assumes all elementary outcomes in a sample space are equally likely. It underpins game theory, decision sciences, risk hedging, and epidemiological models.