How to use the vig calculator
Enter American odds (ex: -110) for each team and view the “Vig %” for the given odds. The vig percentage represents how much “vig” or “vigorish” the sportsbook is charging you. This is also known as “juice” or “hold” in the sports betting industry.
The vig tells you how much the sportsbook is making when it offers a two sided bet. The higher the number, the more the sportsbook is making.
Use the calculator to find bets that minimize the vig. This will help you have a better chance of winning in the long run in sports betting.
For example, if you enter odds of -250 and +250, that would mean the vig is 0. This is a great scenario for the bettor as it means it is essentially a 50/50 bet without having to pay anything extra. The equivalent would be someone giving you 50/50 odds on a coin flip.
How to calculate market hold
Another way to use the vig calculator is to calculate market hold.
Market hold is the vig percentage across multiple different sportsbooks, choosing the best price from each side.
The benefit of doing this line shopping is that you will often bet at much better prices than you would have at a single sportsbook.
Take the image above for example. If you wanted to bet on a side for the Cincinnati Bengals at Pittsburgh Steelers, you can see the odds across multiple different sportsbooks.
If you only bet at DraftKings Sportsbook, then you would either bet on Cincinnati at +163 or Pittsburgh at -200. Entering those two values in the calculator shows a 3.4% hold. That means that DraftKings is making ~4.7% on this market on average.
However, you can see that William Hill is offering +175 on the Cincinnati Bengals while FanDuel Sportsbook is offering -190 on the Pittsburgh Steelers. If you were signed up at either of these sportsbooks, then you could bet at these improved prices.
Entering these two values into the calculator outputs a market hold of 1.9%. That means you have saved ~60% of the cost you would have paid by just choosing between the two sides on DraftKings (1.9% / 4.7%).