What Is the Vig? Understanding How Sportsbooks Make Money

If you've ever wondered how sportsbooks stay in business, the answer is the vig (short for vigorish, also called "juice"). It's the commission sportsbooks charge on every bet, and understanding it is essential for any bettor who wants to be profitable long-term.

How the Vig Works

In a perfect market, a 50/50 bet would pay even money (+100 on both sides). But sportsbooks need to make money, so they adjust the odds. Instead of +100/+100, you'll typically see -110/-110.

At -110 odds, you must bet $110 to win $100. If the sportsbook balances its action evenly on both sides, they collect $110 from the losers and pay out $100 to the winners, pocketing $10 regardless of the outcome.

Calculating the Vig

To calculate the vig on a two-way market, first convert both sides to implied probability, then use this formula:

Vig = [(Total Implied Probability - 100) / Total Implied Probability] × 100

Example

For a -110/-110 market: Each side has 52.38% implied probability. Total = 104.76%. Vig = (104.76 - 100) / 104.76 × 100 = 4.54%

Why It Matters for Bettors

The vig is the hurdle you must overcome to be profitable. With a 4.5% vig, you need to win more than 52.4% of your bets at -110 just to break even. This is why finding reduced juice lines (-105 instead of -110) is so valuable over the long run.

Finding Lower Vig Markets

• Shop lines across multiple sportsbooks
• Look for books offering -105 juice on spreads
• Check for odds boost promotions
• Consider betting exchanges with lower commission rates

The Bottom Line

The vig is a fact of sports betting, and you can't avoid it entirely. But by understanding how it works and actively seeking better lines, you can minimize its impact on your bankroll and give yourself the best chance at long-term success.