A no-vig calculator, or no-vigorish calculator, is a sports betting tool that removes the bookmaker’s built-in commission from betting odds to reveal the true implied probability of each outcome. The vigorish, also called juice or vig, is how sportsbooks profit regardless of the game outcome by setting lines that add up to more than 100 percent probability. By removing the vig, the calculator shows the fair probability of each side winning as estimated by the market. This helps bettors compare the true odds with different sportsbook lines to identify value bets and inefficiencies.
No-vig calculators are widely used by professional sports bettors and sharp betting communities to evaluate line value across sportsbooks. The most common method is the multiplicative method, which normalizes the over-round by proportionally adjusting each side’s implied probability. For two-way markets like moneylines, the calculation is straightforward. For futures or three-way markets, the scaling is applied across all outcomes. Comparing your own probability estimates against no-vig odds allows bettors to identify situations where they believe a team is more likely to win than the true market probability suggests. Free no-vig calculators are available through odds comparison sites like Oddschecker, SBR Odds, and various sports betting analytics platforms.