Overround vs Vig
What each means, how they relate, and when to use which.Overround and vig describe the same built-in edge from two angles. The vig is the cut a bookmaker takes by pricing every selection slightly worse than fair. Because of that, the implied probabilities across a market add up to more than 100%, and that excess is the overround. The vig is what the book does; the overround is how it shows up in the odds.
The bookmaker's built-in margin, visible when the odds across all outcomes of a market imply probabilities that add up to more than 100%.
Use it when Use overround for how far a market's implied probabilities sum above 100%.
Full definition of Overround →The vig is the commission a sportsbook builds into its odds so that the prices for a market add up to more than 100%, giving the book its margin.
Use it when Use vig for the cut the bookmaker takes by shortening the odds.
Full definition of Vig →The key distinction
- Cause and effect: the vig is the odds-shortening the book applies; the overround is the resulting total above 100%.
- The vig is the mechanism you pay; the overround is how you detect and measure it in a market's prices.
- They are related but not identical figures: vig, overround, margin and hold are calculated slightly differently, so treat them as distinct numbers.
Common questions
What's the difference between Overround and Vig?
Overround and vig describe the same built-in edge from two angles. The vig is the cut a bookmaker takes by pricing every selection slightly worse than fair. Because of that, the implied probabilities across a market add up to more than 100%, and that excess is the overround. The vig is what the book does; the overround is how it shows up in the odds.
What is Overround?
The bookmaker's built-in margin, visible when the odds across all outcomes of a market imply probabilities that add up to more than 100%.
What is Vig?
The vig is the commission a sportsbook builds into its odds so that the prices for a market add up to more than 100%, giving the book its margin.
More term comparisons
Understanding, not advice. This explains how two terms differ so you can read the industry clearly. Nothing here treats gambling as a way to make money; the maths favours the house. 18+.