Vig (Bookmaker Margin) Calculator
Reveal the bookmaker's margin in a market and the fair, vig-free probabilities behind the odds.
How to use the vig calculator
- Enter the decimal odds for both sides of the market.
- Click Calculate.
- See the vig, overround and the de-vigged fair probabilities.
Finding fair odds
Removing the vig spreads the margin proportionally to reveal each outcome's fair probability — the number to compare against your own estimate when hunting for value.
Frequently asked questions
What is the vig?
The vig (or juice) is the bookmaker's built-in margin. It is why the implied probabilities of both sides add up to more than 100%.
What is a typical vig?
Mainstream markets often carry a 4–6% margin. Lower vig means better value for the bettor, so comparing margins across books is worthwhile.
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