No-Vig Odds
No-vig odds are betting odds with the sportsbook margin (the vig) removed, expressed as the true implied probabilities that sum to exactly 100%.
A sportsbook builds its margin directly into the price it offers, so the implied probabilities of the two sides of a market always add up to more than 100%. That excess — typically 4% to 8% on a standard two-way market — is the vig. No-vig odds strip that margin back out, rescaling each side so the probabilities sum to exactly 1. The result is the market’s honest estimate of each outcome’s likelihood, independent of the book’s built-in profit cushion.
The most common method is the multiplicative (proportional) approach. Convert each American price to an implied probability, sum them to get the overround (e.g. 1.045 for a 4.5% margin), then divide each raw probability by that sum. For example, two sides priced at -110 each imply 52.38% apiece, summing to 104.76%; dividing each by 1.0476 yields 50% / 50% no-vig. Converting those fair probabilities back to odds gives the no-vig line.
No-vig odds are the foundation of value and expected-value analysis. By comparing a sharp book’s no-vig price against the price you can actually bet elsewhere, you can identify when a line is mispriced in your favor. They are also used to build market consensus, devig player props, and benchmark one book’s number against the rest of the field.