A sportsbook doesn’t need to know who wins. It makes money by charging a small fee on every bet, built into the prices. That fee is the vig, short for vigorish and also called the juice. Once you can see it, you can remove it, and the odds start telling you what the market actually thinks.
What −110 means
A price of −110 means you risk $110 to win $100. To break even at that price, you need to win 52.38% of the time: 110 ÷ (110 + 100).
| Price | Risk to win $100 | Break-even win rate |
|---|---|---|
| +100 | $100 | 50.00% |
| −105 | $105 | 51.22% |
| −110 | $110 | 52.38% |
| −115 | $115 | 53.49% |
| −120 | $120 | 54.55% |
A fair coin flip, priced fairly, would be +100 on both sides. Sportsbooks list it at −110 on both sides instead. The gap between those prices is the fee.
The prices add up to more than 100%
Turn each price into the probability it implies, and add the two sides:
Tails −110 → 52.38%
Total → 104.76%
In a fair market the two sides would add up to exactly 100%. The extra 4.76% is the overround: the margin built into the prices.
What the book actually keeps
The overround is not quite the book’s cut. Suppose the book takes $110 on each side of a −110/−110 market. It holds $220. Whichever side wins collects $210: their $110 back plus $100 in winnings. The book keeps $10, or 4.55% of the money wagered. That is the hold.
1 − 1 ÷ 1.0476 = 4.55%
That $10 is only locked in when the money on each side is balanced. If most bets land on one side, the book has a position and can lose on that game. Books manage this by moving the line, adjusting prices and limiting bet sizes. Over thousands of bets, the hold is their expected profit, not a guarantee on any single game.
How much vig different bets carry
| Example | Prices | Overround | Hold |
|---|---|---|---|
| NFL spread or total | −110 / −110 | 4.76% | 4.55% |
| Player prop | −115 / −115 | 6.98% | 6.52% |
| NBA player points, priced to one side | −120 / −100 | 4.55% | 4.35% |
| Moneyline | −150 / +130 | 3.48% | 3.36% |
These are illustrations; real margins vary by book, sport and market. As a rule, player props, alternate lines, parlays and futures carry more vig than main spreads and totals, so the same opinion costs more to bet there.
Removing the vig
To see what the market really thinks, strip the margin out. This is called devigging. The simplest way divides each side’s implied probability by the total:
For the coin flip, 52.38% ÷ 104.76% = 50%, back where it should be. For a moneyline of −150 and +130:
| Side | Price | Implied | No-vig | Fair odds |
|---|---|---|---|---|
| Favorite | −150 | 60.00% | 57.98% | −138 |
| Underdog | +130 | 43.48% | 42.02% | +138 |
| Total | 103.48% | 100.00% |
So the market’s no-vig estimate is that the favorite wins about 58% of the time, a fair price of −138. Betting the favorite at −150 means paying for 60%.
This is the proportional method, the most common one. Other methods, such as the power and Shin methods, put more of the margin on the longshot. On an even −110/−110 market they all agree; on lopsided prices they can differ by a percentage point or so.
Why this matters
- Compare opinions to the fair price. If you think the favorite above wins 59% of the time, you disagree with the market by about one point (59% vs. 58%), even though the −150 price makes it look like you’re below the market. And at −150 you still need to win 60% just to break even.
- Know your break-even. Winning half your bets at −110 loses money. You need 52.38%.
- Shop for lower vig. Taking the best price on each side across several books can cut the margin sharply. Our guide to synthetic hold shows how.
- Make sure the bets match. Devigging only works when both sides are graded the same way. Check your book’s house rules: NFL, NBA, MLB, NHL.
Prediction markets charge their fee differently, as a trading fee rather than built into the price. The Kalshi odds converter puts a Kalshi price and its fee on the same footing as a sportsbook line.
Quick formulas
Positive odds: implied = 100 ÷ (odds + 100)
Overround = sum of implied − 100%
Hold = 1 − 1 ÷ sum of implied
No-vig = implied ÷ sum of implied
Frequently asked questions
What is vig in sports betting?
Vig, short for vigorish and also called juice, is the sportsbook’s fee built into the odds. It is why both sides of an even matchup are priced at −110 instead of +100.
How much vig is in −110 odds?
With −110 on both sides, the implied probabilities add up to 104.76%, an overround of 4.76%. The book’s hold, the share of money wagered it keeps when action is balanced, is about 4.55%.
What is the difference between vig, overround and hold?
Vig is the general name for the fee. Overround is how far the implied probabilities add up above 100%. Hold is the share of all money wagered the book expects to keep: 1 minus 1 divided by the total of the implied probabilities.
How do you remove the vig from betting odds?
Convert both sides to implied probabilities, add them up, and divide each side by the total. For −150 and +130, 60.00% and 43.48% add to 103.48%, so the no-vig probabilities are 57.98% and 42.02%.
Related reading
- Synthetic Hold: How to Find the True Price of Any Betting Market
- Opening Lines vs. Closing Lines: Why Sharp Bettors Bet Early
- Kalshi Odds Converter
This guide replaces an earlier 2025 post at this address.
← Back to Blog