Vig / No-Vig Calculator
Calculate the bookmaker margin (vig/vigorish) and find the true fair odds by removing the overround from any market.
| Outcome | Odds | Implied | True Prob | Fair odds: {odds} |
|---|---|---|---|---|
| Outcome 1 | 1.90 | 52.6% | 50.0% | 2.00 |
| Outcome 2 | 1.90 | 52.6% | 50.0% | 2.00 |
What is Vig (Vigorish)?
The vig (also called juice, margin, or overround) is the bookmaker’s built-in profit margin. It is the reason the implied probabilities of all outcomes in a market add up to more than 100%.
How to Calculate Vig
Add up the implied probabilities of all outcomes. The amount above 100% is the bookmaker’s margin.
Example: Tennis Match
Player A at 1.80 (implied 55.6%) and Player B at 2.05 (implied 48.8%):
- Total: 55.6% + 48.8% = 104.4%
- Vig = 4.4%
Fair (No-Vig) Odds
To remove the vig and find the true odds:
- Player A fair probability: 55.6% / 104.4% = 53.3% → Fair odds: 1.877
- Player B fair probability: 48.8% / 104.4% = 46.7% → Fair odds: 2.141
Why Fair Odds Matter
Knowing the fair odds helps you: compare value across different bookmakers, identify which side has more value, set accurate probabilities for value betting, and calculate optimal Kelly Criterion stakes.
Vig Distribution Methods
Different bookmakers distribute their margin differently. Some load it equally on both sides (“multiplicative”), others load more on the favourite (“favourite-longshot bias”). Our calculator shows you the true odds using proportional margin removal.
What is a Good Vig?
Sharp bookmakers like Pinnacle typically have 2-3% margins. High-street bookmakers often run 5-10%+. Lower vig means better value for bettors.