Implied probability calculator

The win rate a price needs to break even. Add the other side to see the market's hold and its no-vig fair probability.

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Every price on our odds screen shows its fair probability (To hit) with the vig removed across books.

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How it works

A price's implied probability is the chance it would need to win for the bet to break even:

implied = 1 ÷ decimal

American +A: decimal = 1 + A/100 · American −A: decimal = 1 + 100/A

The implied probability still includes the book's margin. Add the other side of the market and the calculator shows the hold (how much the two sides add up past 100%) and the fair probability with the vig removed, by multiplicative and by probit.

Worked example

−150 is decimal 1.6667, so it implies 60.00%: the bet breaks even if it wins 60% of the time.

With the other side at +130: implied 60.00% + 43.48% = 103.48% → hold 3.48%

No-vig fair for −150: multiplicative 57.98%, probit 58.27%

American	Decimal	Implied
−300	1.333	75.00%
−200	1.500	66.67%
−150	1.667	60.00%
−110	1.909	52.38%
+100	2.000	50.00%
+120	2.200	45.45%
+150	2.500	40.00%
+200	3.000	33.33%
+300	4.000	25.00%

Things to watch

Implied is not fair. It includes the vig; the fair chance is lower for both sides.
One price is not a market. To estimate a true probability, devig several books' two-sided prices.

Frequently asked questions

What does −150 mean as a probability?

−150 is decimal 1.6667, so the implied probability is 1 ÷ 1.6667 = 60%. You need to win more than 60% of the time to profit at that price.

Why do both sides add up to more than 100%?

That excess is the book's margin, the hold. −110 on both sides implies 52.38% each, 104.76% in total.

How do I get the true probability?

Remove the vig with a devig method, ideally across several sharp books. The no-vig calculator does it for one market.

Is implied probability the same as break-even win rate?

Yes, for a single bet at that price.

Related calculators

Odds converterAmerican, decimal, fractional, probability, HK, Malay, Indonesian.No-vig fair odds calculatorFair odds with five devig methods side by side, 2- to 6-way markets.Expected value (EV) calculatorEV, edge and Kelly from a fair %, fair odds or a two-sided market with the vig removed.Hold (market vig) calculatorA market's hold, its band (arb, near-arb, low, standard) and fair prices.

Learn more

Intro to +EV bettingPositive expected value means a price pays more than its fair odds. Here's how to find the fair odds and what the edge really means.Devig methods compared: multiplicative, additive, power, Shin, probitFive ways to take the vig out of a price, when they agree, when they don't, and which one we use by default.