No-Vig Calc
Cut the margin and see the fair, vig-free price.
How to Use This Calculator
- Choose your odds format (Decimal, Fractional, or American)
- Enter the bookmaker’s odds for every outcome in the event
- Add or strip out outcomes as the market demands
- Read off the fair odds (vig stripped away), fair probabilities, and the bookmaker’s overround
The overround lays bare exactly how much extra probability the bookmaker has packed in as their margin.
Formula
Step-by-step process:
- Convert all odds to implied probabilities
- Sum the probabilities (will exceed 100%)
- Divide each probability by the total to get fair probabilities
- Convert fair probabilities back to odds
Overround (Vig) = Total Implied Probability - 100%
Frequently Asked Questions
What's the vig, or juice?
The vig (vigorish), or juice, is the bookmaker’s built-in margin. It guarantees the bookmaker turns a profit no matter the result — it’s the gap between the total implied probabilities and 100%.
What counts as fair odds?
Fair odds are what you’d see if the bookmaker ran a zero-margin book. They reflect the genuine market-implied probability of each outcome.
How much vig is typical?
Sharp bookmakers usually run a 2-3% overround, while recreational books can stretch to 5-7% or beyond. Less vig means sharper odds in your favour.