Probability Calculator

Find the probability of an event and its odds ratio.

How to use

Enter favorable outcomes and total outcomes.

Formula

P = favorable / total; odds = favorable : (total - favorable).

Examples

  • 3 of 10 → 30%, odds 3:7

Important notes

Assumes equally likely outcomes.

Frequently asked questions

What are odds?

Ratio of favorable to unfavorable outcomes.

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