Game Theory & Decision

Basic

Odds to Probability

Convert betting odds into an implied probability.

Formula

p = \frac{o}{1 + o}

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Variables

pProbability

oOdds (to 1)

Example

Odds of 3:1 against (o=1/3): p = 0.25

Did You Know?

Bookmakers' implied probabilities always sum to over 100% — the excess is their built-in margin.

game theory odds probability

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