Vig Calculator
Enter both sides of a two-way betting market. Anything above 100% combined implied probability is the estimated sportsbook margin — also called vig or hold.
A perfectly fair two-way market would total 100% implied probability. Anything above 100% represents estimated sportsbook margin. The hold is an estimate of how far the market is priced above fair — it is not the exact profit the sportsbook will realize on any single outcome.
Example
A standard point spread at -110 / -110 implies 52.38% on each side. The combined implied probability is 104.76%, so the estimated hold is 4.76%.
After removing that margin proportionally, each side has an estimated fair probability of 50%. A market priced at -105 / -105 would combine to 103.49%, giving a smaller estimated hold of about 3.49%.
What the results mean
- Implied probability
- The break-even win rate each posted price demands. Both sides include the sportsbook's built-in margin.
- Combined implied probability
- The two implied probabilities added together. In a fair market this would equal 100%.
- Estimated sportsbook hold
- How far past 100% the market is priced. This is the estimated margin, not a guaranteed profit figure.
- Fair probability after de-vigging
- Each side's estimated chance after the margin is removed proportionally. The two fair probabilities sum to 100%.
Frequently asked questions
Keep reading
- How sportsbook vig works — why every price carries a built-in margin
- Why parlays carry more vig — the margin compounds with every leg
- Fair Odds Calculator — turn de-vigged probabilities back into odds
Analyzing a full parlay? Let EVScout check every leg automatically.
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