Find the probability of an event as a decimal, percent and odds — plus the chance that several independent tries all succeed.
How probability is worked out
Enter the favorable and total outcomes and this calculator returns the probability in several forms, along with the odds. Add a number of independent tries to see the chance they all succeed.
It’s the everyday tool for dice, cards and simple chance questions.
Using the calculator
- Enter the favorable outcomes.
- Enter the total possible outcomes.
- Add a number of tries for the all-succeed probability.
The calculation
probability = favorable ÷ total
all of k tries = probability^k
Worked example
The calculator opens with a independent tries of 1. On those figures the probability is 0.1667. Underneath, As percent comes out at 16.67% and Odds for at 1 : 5. Change any field and every figure updates as you type.
Common questions
How do I calculate probability?
Divide the number of favorable outcomes by the total number of equally likely outcomes.
What are odds vs probability?
Probability compares favorable to total; odds compare favorable to unfavorable. A 1-in-6 probability is 1:5 odds.
How do I find the chance of several events?
For independent events that must all happen, multiply their probabilities — which this tool does for repeated identical tries.