No-Vig Fair Odds Calculator

The No-Vig Fair Odds calculator removes the sportsbook’s built in margin from a market so you can see the true underlying probabilities. Sportsbooks price both sides of a market with an embedded edge known as the vig or overround. This margin ensures the book profits regardless of outcome, but it also distorts the true implied probabilities.

By entering both sides of a two outcome market, the calculator converts each price into implied probability and then normalizes them so they sum to 100 percent. The result is a set of “fair” odds that reflect the market’s unbiased expectation rather than the sportsbook’s marked up price.

For example, if both sides of a market are priced at -110, the implied probabilities add up to more than 100 percent due to the vig. Removing that margin reveals the fair probability of each side and the corresponding true odds.

Understanding fair odds is critical for identifying value. If another sportsbook offers a price better than the calculated fair number, that discrepancy may represent positive expected value. This tool is especially useful for comparing markets across books and evaluating whether a line is overpriced.