Free Tool

Implied Probability Calculator

Convert any odds into the true percentage chance they represent, and find the fair odds with the bookmaker's margin removed. Add multiple outcomes to see the full market breakdown.

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What Is Implied Probability?

Implied Probability

The percentage chance of an outcome occurring according to the bookmaker's odds. Odds of 3.00 imply a 33.33% chance. It overstates true probability due to margin.

Fair Odds

The odds you'd receive if the bookmaker had zero margin. Fair odds are always higher than offered odds, representing the "true" probability of the event.

Bookmaker Margin

Also called overround or vig. It's the percentage by which the total implied probabilities exceed 100%. This is how bookmakers ensure a profit regardless of the outcome.

Finding Value

If your estimate of an outcome's probability is higher than the implied probability from the odds, that bet has positive expected value (EV+).