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Calculate odds from probability

Convert probability p to decimal, fractional, and American odds.

Also known as: calculate odds from probability calculator, probability to odds calculator, calculate odds from probability, probability math, probability calculate odds from probability

Inputs

Results update when you click Calculate.

Decimal odds

4.00

Odds for : against

1 : 3.00

American (approx.)

300

Percent

25.00%

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What this result means

Convert probability p to decimal, fractional, and American odds. Decimal odds = 1/p. Odds against = (1−p)/p.

Assumptions

  • Rule dependency: Universal formula.

How is it calculated?

Decimal odds = 1/p. Odds against = (1−p)/p.

Example

p = 0.25 → decimal odds 4.00 (3 to 1 against).

Frequently asked questions

Implied probability?+

Implied p = 1 / decimal odds (ignoring vig).