Bookmaker Margin Calculator
Calculate sportsbook margin, overround, payout percentage, implied probabilities and no-vig fair odds from decimal odds.
Calculate sportsbook margin from odds
Bookmaker margin, also called overround or vig, is the extra probability built into a market. Add the implied probabilities from all decimal odds; the amount above 100% is the margin.
A 106% book has about 6% overround.
No-vig probabilities and fair odds
The calculator normalizes implied probabilities to remove the market overround, then converts those no-vig probabilities back into fair decimal odds.
Frequently Asked Questions
Sources and References
- OverroundWikipedia
- VigorishWikipedia
- Responsible gamingAmerican Gaming Association
- Help and treatment resourcesNCPG
Calculations are based on the listed reference sources. Links open in a new tab.
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