How are sports betting odds calculated?
Sports betting odds are calculated with the main goal for sportsbooks being to receive equal money on both sides of a bet.

For example, if the Kansas City Chiefs were a -10 point favorite against the Oakland Raiders and were 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. 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). 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.

That's because of the vig, or the amount the sportsbook charges for taking a bet. 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. Say there is one bet on each side, $110 to win $100. If the Chiefs win by seven points and don't cover, the Chiefs bettor is out $110, while the Raiders bettor is up $100. That extra $10 goes to the sportsbook because of the -110 odds and that's why the sportsbook wants equal money.

To understand how odds are calculated, it's best to learn what they specify. Sports betting odds and lines specify the implied probability of an outcome and how much money can be won.

Odds can refer to moneylines, spreads or total batches, and they can be displayed as American, British (fractional) or European (decimal). While odds look different, they mean the same thing.