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Odds converter

Different formats, the same mathematical price. Convert odds and understand the implied probability.

Choose a format

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What the formats mean.

Fractional odds describe profit relative to the stake. Decimal odds include the returned stake. American odds express the profit on a 100-unit stake for a positive price, or the stake needed for 100 units of profit for a negative price.

Decimal odds1 + fractional oddsImplied probability100 ÷ decimal odds

For 8/1, decimal odds are 9 and the implied probability is approximately 11.1111%. This number does not remove an operator’s margin or establish the true chance of an outcome.

Precision and supported inputs

Fractional output is reduced to its exact ratio. Decimal output is rounded to six decimal places, American output to two, and probability to four. Decimal odds must be greater than 1; American odds must be at least +100 or at most −100.

Read betting odds explained for the reasoning behind these formats, see the calculation methodology, or use the each-way calculator for a return breakdown.