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Result
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Enter your details to calculate.
Decimal probability
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Odds for
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How to calculate probability
Compare the number of favourable outcomes with all possible outcomes.
1
Count favourable outcomes
Enter how many outcomes meet the condition you are interested in.
2
Enter total outcomes
Enter the complete number of equally likely possible outcomes.
3
Interpret the result
Read the decimal, percentage, and odds for the favourable outcome.
Frequently Asked Questions
What is probability?
Probability is the chance of an event occurring, expressed from zero to one.
How is probability calculated?
Divide favourable outcomes by total outcomes.
Can favourable outcomes be zero?
Yes. Zero favourable outcomes gives a probability of zero.
Can probability be 100 percent?
Yes. When every outcome is favourable, probability is one or 100 percent.
Why must outcomes be whole numbers?
The calculator describes counts of outcomes, so it accepts safe whole numbers.
What are odds for?
Odds for compare favourable outcomes with unfavourable outcomes.
Can favourable outcomes exceed total outcomes?
No. The favourable count must be between zero and the total.