- Choose Mode — Single event, multiple events, or coin/dice.
- Enter Values — Favorable/total outcomes or probabilities.
- Calculate — See probability, odds, complement, and combined probabilities.
Probability Calculator — Odds & Chance
The Probability Calculator offers three modes for computing probabilities. Calculate single event probability with odds and complement, combine multiple independent events, or explore coin flip and dice roll outcomes.
Three Modes
- Single Event — Enter favorable and total outcomes. See probability, percentage, odds, and complement.
- Multiple Events — Enter P(A) and P(B). See P(A and B) and P(A or B) for independent events.
- Coin/Dice — Calculate probability of all heads for N coins and total outcomes for N dice.
Key Formulas
- Basic: P = Favorable ÷ Total
- Complement: P(not A) = 1 - P(A)
- And (independent): P(A∩B) = P(A) × P(B)
- Or (independent): P(A∪B) = P(A) + P(B) - P(A∩B)
Privacy
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