Remember that every spread still has a moneyline attached to it. While that might be a bit confusing, all that refers to is the cost of betting the spread; not how the outcome will be decided. For example, if someone says to you that “the Patriots are laying three points but I have low juice, so my moneyline is -104”, what they are referring to is the price of betting the spread. That merely means that they are betting the spread but the moneyline attached to betting that spread is -104.
Oftentimes you’ll see a point spread that has a half-point added to the number. Of course, there’s no such thing as half a point in a football game, so why do we so often see point spreads with a (.5) attached to the score? Sportsbooks do this to make sure there isn’t a chance of a push. Let’s take another look at our game from above with the half point added.
Here’s an analogy. Remember when you played basketball growing up with your older brother or the older kid from down the street? It wasn’t fair if you played straight up, so they would spot you a few points to try and even things out. For example, let’s say you decided that you would play to 10 points. They might spot you 5 points in order to try and make things fairer.
The two results above are the no-vig probabilities. If you're sharp, you'll notice that adding 68.57% and 31.43% up together will give you 100%. The extra 2.95% has been removed, so there's no more vig. We can now go to our odds converter and enter 68.57% into the implied probability field. This will give us moneyline odds of -218. If we enter 31.43%, we'll get moneyline odds of +218. The original moneyline market of the Celtics at -240 and the Grizzlies at +210 therefore has no-vig odds of the Celtics at -218 and the Grizzlies at +218.
The point spread, which is sometimes referred to as the “handicap”, is the number of points taken from the favorite, or given to the underdog, in order to open up the chances of either team winning the wager evenly. In most games, there’s usually a team that is more likely to win, based on a number of statistical factors. If the only kind of wager available was on who would win between a very strong team and a poor team, it wouldn’t be all that exciting. The point spread was designed to make betting much more interesting, since it allows a bet on the losing team to win you money. How? Let’s break down an example: