If you’re new to sports betting, it can be an intimidating place.
My dad—someone who loves spending an NFL Sunday inside a sportsbook more than he loves me—didn’t know what any of the numbers meant until I explained them to him a few years ago. All that information can be a bit overwhelming, and no one likes to feel like they’re the only person in the room who doesn’t know what’s going on.
Sports betting has also seen a massive spike in popularity as of late, with more and more states rolling out legalized sports betting on a yearly basis. That has brought a host of new bettors into the space who might need a little help getting started.
Consider me your sports betting sherpa in this climb to the top of Mount Everest. Whether you’re just starting out or simply looking for a refresher, I’m going to break down everything you need to know related to betting lines. The next time you walk into a sportsbook or log into your online betting account, all those different numbers are going to start looking like dollar signs.
Let’s dive in.
What are sports betting odds?
Sports betting odds are the great equalizer. Very rarely will two teams meet up and be considered exactly equal, which creates a dilemma for the sportsbooks. They can’t let the betting public just pick a winner between two uneven teams—otherwise they would go out of business in a hurry. If you could simply win $100 on a $100 bet every time the Chiefs beat the Texans, we could all get rich quickly.
With that in mind, the sportsbooks have come up with two different ways to level the playing field: point spreads and moneylines. They allow teams of different calibers to attract betting interest on both sides, albeit in different ways.
The point spread
These are most commonly used in football and basketball betting, but they exist in other sports as well. Essentially, point spreads look to level the playing field by requiring the favorite to win by a certain number of points.
Dec 18, 2022; Houston, Texas, USA; Kansas City Chiefs quarterback Patrick Mahomes (15) runs with the ball during the fourth quarter against the Houston Texans at NRG Stadium. Mandatory Credit: Troy Taormina-USA TODAY Sports
Let’s look at an example. In our previous example, the Chiefs were playing the Texans. Those two teams met in Houston during the 2022-23 NFL season, and the betting line looked like this on FanDuel Sportsbook:
Kansas City Chiefs (-14.5) at Houston Texans
In that contest, the Chiefs were considered the favorites. They entered that contest at 10-3, while the lowly Texans were just 1-11-1. In order to cover the spread in that scenario—and for the people who bet on the Chiefs to cash their tickets—the Chiefs would have to win the game by at least 15 points.
That is what the “minus” sign means in -14.5. You’re betting that the Chiefs’ final score will be at least 14.5 points higher than the Texans’ final score.
If the Chiefs lose the game outright or win the game by less than 14 points, the Texans would be considered the winners in the eyes of the spread. Since the Texans are the underdog, their spread would be listed as +14.5. If their final score is within 14.5 points of the Chiefs’ final score, they cover the spread.
Betting on a favorite—otherwise known as “laying the points”—typically means you are going to be betting on the superior team, but it also means they’re going to have to play well to cover. Taking the underdog—or “grabbing the points”—means you’re expecting the game to be closer than anticipated.
Occasionally, you will see two teams that the oddsmakers deem perfectly even. In those instances, the game will be listed as a pick’em or PK. That means that whoever wins the game will be considered the winner on the spread as well.
When the final score lands exactly on the spread—for example, if a seven-point favorite wins by exactly seven—that is considered a push, and those who bet on the favorite and underdog will both receive their initial wagers back.
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The moneyline
The moneyline works in a far different way than the point spread, but the concept is similar. Instead of having to win by a certain number, the price that you have to pay is far different for the favorite and the underdog. Essentially, the wins that you can receive on the favorite are far lower than the potential wins with betting the underdog.
Moneyline wagers are the most common form of betting in MLB and the NHL, but they are also available for the NFL, NBA, soccer, and college sports.
Going back to our Chiefs-Texans example, the moneyline odds for that contest might look something like this:
- Chiefs ML (-750)
- Texans ML (+500)
Moneyline odds can be a bit more confusing than spread odds, but the premise remains the same. Anytime you see a minus sign, you should think about giving. When you see a plus sign, it’s receiving.
Moneyline odds are all centered around a hypothetical $100 bet. Since the Chiefs are the favorite in our example, you would need to bet $750 in order to win $100. You don’t need to bet those exact figures, but for every dollar you want to win on the Chiefs, you would need to risk $7.50.
On the other hand, the Texans are sizable underdogs. They’re listed as +500, meaning that a $100 bet would return $500 in profit. In other words, for every dollar that you risk on the Texans, you would get back $5 profit if they won.
The goal here is not to make the two teams level on the field, but rather their impact on your wallet. The Chiefs may win this game six straight times, but if you bet the same amount on the moneyline and they lose the seventh, that would result in you losing money overall.
Conversely, if the Texans lost four straight to the Chiefs but won the fifth, you would be up if you bet the same amount at the same odds for all five games.
Converting moneyline odds to implied probabilities is helpful when determining which lines are the best. In our example, the Chiefs being listed as -750 favorites translates to an implied probability of 88.24%. If you think the Chiefs have a better than 88.24% chance of beating the Texans, then they would technically grade out as a value. Of course, there still isn’t a ton of upside in betting a -750 favorite, but the math would support doing so.
At +500, the Texans’ implied probability checks in at 16.67%. If you think their odds are greater than 16.67% of pulling off the upset, then they stand out as the correct side.
Knowing the math is half the battle with moneyline bets, and it’s why shopping for the best price is so crucial in sports betting. The difference between -120 and -125 may not sound like much, but you’re going to need to win at a higher rate in the long run if you’re consistently betting worse numbers.
Types of betting odds
American odds
So far, all the sports odds I’ve referred to are considered “American odds.” Those are the wagers that revolve around a hypothetical bet amount of $100. Any negative number means you need to bet that much in order to win $100, while any positive number means that risking $100 will net you that much in profit.
Just to hammer the point home, let’s look at an example from DraftKings Sportsbook:
In this game, there are three different wagers you can make: the spread, the over/under, and the moneyline. For the spread and total wagers, both teams are listed as -110. That means you would need to bet $110 in order to win $100, regardless of which side you choose.
The final numbers are the moneyline odds. Since the Celtics are favorites, they have negative odds, and you need to risk $145 in order to win $100. As underdogs, the Raptors have positive odds, so they would return $125 profit on a $100 bet if they were victorious.
-110 odds are the most common for spread and total bets. This is considered the industry standard, and it’s part of how Vegas makes its money.
Even though the point spread is leveling the teams on the surface, the extra 10 cents is called “juice” or “the vig.” This is what you have to pay the sportsbook for the right to choose which game you want to bet. They have to post the lines for every single game in basically every major sport, so the 10-cent vig is our penalty for being able to cherry-pick.
Unsurprisingly, American odds are not all that common outside of America. There other two other very popular ways to display odds around the globe: fractional odds and decimal odds.
Fractional odds
Fractional odds are actually pretty similar to American odds—they just don’t assume a $100 wager. The odds are instead displayed as a fraction, and multiplying your wager by that fraction will show the potential profit.
Just in case you need a quick brush-up on your fractions, they consist of two parts: the top number, also known as the numerator, and the bottom number, aka the denominator. If the numerator is greater than the denominator, the fraction has a value greater than one. If the denominator is larger, the fraction is less than one.
Let’s look at another example:
This is another NBA game on DraftKings Sportsbook, this time with the odds displayed fractionally. Both the point spread bets and total bets are now listed as 10/11, which is identical to -110 in the American standard. If you take $110 and multiply it by 10/11, it comes out to $100.
The bigger change is with the moneyline odds. The Knicks—who are the favorites in this contest—are now listed at 5/9, while the Pacers are listed at 31/20.
To find out exactly how much those teams would pay out, simply take your desired bet and multiply by the odds. A $100 bet on the Knicks would return $55.55 in profit, while a $100 wager on the Pacers would return $155. You also receive your initial wager back if you win, so the fractional calculation is simply done for the profit.
Whenever you see fractional odds, any number that is smaller than one is going to be a bet on the favorite, while a bet that is larger than one is a bet on the underdog.
Fractional odds are pretty common in the futures market. If you’re saying that a team has 6-1 odds to win the Super Bowl, those are technically fractional odds. It means that every $1 that you bet will return $6 of profit if that team ultimately wins.
Decimal odds
Decimal odds are similar to fractional odds, with one major exception. Both can tell you how much you stand to win by multiplying your initial wager by the selected odds. However, while fractional odds only tell you how much profit you’ll receive if your wager wins, decimal odds also include your original wager.
Let’s dive into another example to see it in action:
This time, the odds for the spread and total are both listed as 1.90. Let’s stick to our hypothetical $100 selection. If you bet $100 on either side, the over, or the under, you would be rewarded a $190 total payout if your bet wins. That includes your original $100 wager, so your bet would be for $90 profit.
For the moneyline, the Bulls are listed at 3.45 while the Bucks are listed at 1.33. That means a $100 winning bet on the Bulls would return $345, including your original wager, while a Bucks win would return $133.
These bets are great if you’re looking to do quick math in your head, especially if you’re betting with even numbers. Betting $100 means you just need to move the decimal point two spots to the right to see the potential payout.
A decimal of 2.00 is considered even odds. Anything above 2.0 is considered an underdog wager, while anything between 1.0 and 2.0 is considered a favorite. You’ll never see anything below 1.0 in decimal odds since 1.0 is the baseline for your original bet.
Most sportsbooks will let you choose your preferred odds format. Most content produced in America will be centered around American odds, but you don’t have to use them if you don’t want to. If decimal or fractional odds make more sense in your head, you should be able to convert your preferred betting site into those odds.
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Using odds converters
Occasionally, knowing how to convert odds from one form to another can be helpful. Maybe you’re in the sportsbook and want to translate the American odds into decimals. Maybe you want to convert futures odds from decimal to fractional.
Whatever the reason, this is where an odds calculator can be your best friend.
You can use our in-house odds calculator to get started (shown below).
In addition to the American, decimal, and fractional odds, you’ll also find implied odds, aka implied probability. These are very useful because they show you the break-even point for your bets depending on the vig.
For example, a standard -110 bet has an implied probability of 52.38%, so you’ll need to hit those wagers at a greater frequency to be a winning bettor. The greater the odds, the greater the percentage you’ll need to hit.
How are betting odds calculated?
Now we’re getting into the good stuff. Now that we know what all the different numbers mean, how do the sportsbooks determine those figures? That’s the million-dollar question.
I like to think of sports betting as more of an art than a science. There are some rules that the sportsbooks follow, but there also is a bit of ambiguity.
The oddsmakers typically start by setting an opening line, also known as an opener. These are primarily made using “power ratings.”
In basketball and football, each team is given a rating as to how much better or worse than average they are. A team like the Chiefs might be considered eight points better than the average NFL team, while the Texans might be considered eight points worse. After adjusting for homefield advantage—which is worth significantly less now than it used to be—that’s how you end up with Chiefs -14.5.
That said, that’s just the starting point. A million other factors can move the line by a point or two. Injuries are the biggest deal, and the player can have a massive impact. The top quarterbacks in football can be worth up to a full touchdown, while a top NBA player can be worth a comparable amount.
Other injuries could be worth a smaller amount, particularly if they pile up at a certain position. For example, if a team is down four starters on their offensive line, that matters a lot more than a team with four injuries sprinkled across all positions.
Sharp bets can also help move the line. When professional bettors that the sportsbooks respect take a stand on the game, that is important information for the bookmakers. If multiple pros are getting down on the same team, it can be an indication that their line is off. They will often adjust the line to compensate, especially if the public is “chasing the steam.”
Other factors that can impact the spread include travel, upcoming schedule, recent workload, and weather.
The point spreads are fluid up until game-time, and grabbing the best number is a great way to be a successful sports bettor. If you can grab the line before it moves, gobbling up key closing line value, it’s a great indicator that you’re on the right side. There’s no guarantee those bets will win in any given game, but it should pay off in the long run.
