The plus (+) and minus (-) in sports betting can refer to either the point spread or betting odds. Understanding plus (+) and minus (-) odds is the most important thing before learning about American odds. The main signifiers of American odds are that they either have a plus (+) or minus (-) in front of them and are in terms of 100. Most sportsbooks in the United States use American Odds. While odds look different, they mean the same thing. Odds can refer to moneyline, spread or total bets, and they can be displayed as American, British (fractional) or European (decimal). Sports betting odds and lines specify the implied probability of an outcome and how much money can be won. To understand how odds are calculated, it's best to learn what they specify. That extra $10 goes to the sportsbook because of the -110 odds and that's why the sportsbook wants equal money. If the Chiefs win by seven points and don't cover, the Chiefs bettor is out $110, while the Raiders bettor is up $100.

Say there is one bet on each side, $110 to win $100. In the above situation, if equal money was put on the Chiefs -10 (-110) and Raiders +10 (-110), the sportsbook would finish in the positive no matter the result. That's because of the vig, or the amount the sportsbook charges for taking a bet. While receiving equal money isn't always possible, it's always the goal because if that's the case, the sportsbook will come out in the positive no matter the final result. And so, the sportsbook will continue to raise the line until the other side starts receiving action (from 10.5 to 11 to 11.5, etc). Sports betting odds are calculated with the main goal for sportsbooks being to receive equal money on both sides of a bet.įor example, if the Kansas City Chiefs are a -10 point favorite against the Oakland Raiders and are getting 90% of the money, the sportsbook would likely adjust their line so they don't finish in the negative if the Chiefs cover that spread.

How sports betting odds are calculated