Over/Under, in plain words
An over/under, also called a total, is a bet on whether a number finishes above or below a line the book sets. For a game it is the combined score of both teams. For a player prop it is one stat, such as points, rebounds or receiving yards.
Most totals end in a half, such as 47.5, so one side has to win. A whole-number total can push, which refunds the bet. The two sides are usually priced near -110 each, but not always: when the book thinks one side is more likely it moves the price before it moves the number, so -125 / +105 on the same 47.5 is a different bet from -110 / -110.
The useful question is not whether the game feels high scoring. It is whether the line and its price imply a chance you disagree with. Wind, pace, injuries and officials can all move a total, and the market usually prices them before kickoff. Totals at different books can disagree by a point or more, which is the starting point for middles.
The idea, drawn
Worked example · illustration
A total of 47.5 at −125 / +105
- Over 47.5
- −125
- Under 47.5
- +105
- Over implies
- 55.56%
- Under implies
- 48.78%
- −125 implies 125 / 225 = 55.56%.
- +105 implies 100 / 205 = 48.78%.
- Together 104.34%; the fair Over is about 53.2% once the margin comes out.
The book has leaned the price toward the Over without moving the number. Read both before you call a total cheap.