Odds from probability Calculator

Free odds from probability calculator to calculate odds from probability. Instant results in your browser — no signup.

JavaScript is required for live calculation.

You can still read how Odds from probability Calculator works, the formula, examples, and FAQs below.

Probability p (0–1)

Direct calculator

Inputs

Probability p (0–1)

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

Free odds from probability calculator to calculate odds from probability. Instant results in your browser — no signup. 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).