Odds Calculator

Calculate odds in favor, odds against, probability, percentage, and simplified ratios from favorable and unfavorable outcomes.

Odds in favor = favorable : unfavorable
Probability = favorable / (favorable + unfavorable)

Result will appear here.
Metric Value

Privacy: calculations run locally in your browser. No inputs are stored or transmitted.

How it works

This tool converts counts into:
odds in favor, odds against, and probability.

If favorable = 3 and unfavorable = 7:
odds in favor = 3:7
probability = 3 / (3 + 7) = 0.3

Examples

  • 3 favorable, 7 unfavorable → probability = 0.3
  • 1 favorable, 1 unfavorable → probability = 0.5
  • 0 favorable, 5 unfavorable → probability = 0

FAQ

  • What are odds in favor?

    Odds in favor compare favorable outcomes to unfavorable outcomes, usually written as a:b.

  • What is the difference between odds and probability?

    Probability is favorable outcomes divided by total outcomes, while odds compare favorable outcomes directly to unfavorable outcomes.

  • Can both favorable and unfavorable outcomes be zero?

    No. At least one of them must be greater than zero, otherwise odds and probability are undefined.

  • Are calculations stored?

    No. Everything runs locally in your browser.

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