Free Probability Calculator
Calculate the probability of an event occurring. Enter the number of favorable outcomes and total possible outcomes.
Probability
0.300000
Probability Pct30.00%
Odds For0.4286
Odds Against2.3333
How to Calculate Probability
Formula
P(event) = Favorable Outcomes / Total Outcomes
Probability ranges from 0 (impossible) to 1 (certain).
Odds
Example Calculation
A bag has 10 marbles: 3 red, 7 blue. What is the probability of drawing a red marble?
- 01P(red) = 3 / 10 = 0.3
- 02As a percentage: 30%
- 03Odds in favor: 3 / 7 ≈ 0.4286
- 04Odds against: 7 / 3 ≈ 2.3333
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