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Sports Betting 101: A Beginner’s Guide to Odds, Spreads, Terminology

Learn what terms like moneyline, against the spread, straight up, over/under mean  in this sports betting primer.

With the rise of sports betting, more and more people will want to get in on the action! But, where and how do you start?

If you’re feeling overwhelmed by looking at a sportsbook’s odds or by the jargon used in Las Vegas, this article is for you! We will look at what moneyline (ML), against the spread (ATS), straight up (SU), over/under (O/U), vig, and what all those plus and minus signs really mean—spoiler alert: it’s actually incredibly simple.

By the end of this primer, you’ll be able to tell people whether you think “the juice is worth the squeeze.”

So, let’s dive in!

First things first: Here are offerings for a game featuring the Brooklyn Nets vs. the Philadelphia 76ers. Let’s look at what you see when you visit an online sportsbook.


Betting the moneyline

Let’s say you are from Williamsburg, and you want to place a bet on the Nets to win this game. You want to take the Nets to win straight up (SU). It doesn’t matter if the Nets win by one point or win by 15 points; you want to bet that the Nets win. This kind of bet is a ML bet. Easy, right? You want to bet the Nets on the ML.

Looking at the above image, you will see the offering for ML bets in the far right column. They are simply listed with a + or - sign. The Nets are +155 on the ML, while the 76ers are -188.

But hold up, WHAT DOES THAT MEAN?!

The plus and minus signs are shorthand to tell you what your payout will be if you win your bet.

If you see a minus sign next to your bet, your payout will be less than 100% of your initial investment if you win the bet. If you see a plus sign, your payout will be more than 100% of your initial investment.

The minus sign on a ML bet also indicates the team is favored. It makes sense, right? The sportsbook will not pay big dividends for betting on the favorite. Conversely, the plus sign on a ML bet indicates the underdog. Sportsbooks are willing to pay out more for the less-likely outcome. In our example, the Brooklyn Nets are the underdog, and the payout will be more than what you initially invested should the Nets win the game.

So, we are taking the Nets on the ML at +155. According to the oddsmakers, this is a bet that you are less likely to win, so if the Nets win, the sportsbook will pay you 1.55 times, or 155% of, your initial investment. If you put $100 on the Nets to win, and they do, your profit will be $155, bringing your total payout $255. So, $100 in and $255 out if the Nets win the game!

Now, let's say our college roommate is a Philadelphia 76ers fan. She is all-in on the Sixers as the favorite and decides to invest her $100 on the Sixers for a -188 payout. Should Philadelphia win this game, her profit would be only $53.19, and her total payout would be $153.19.

To put it in even simpler terms, at -188 odds, she would have to invest $188 for a $100 profit.

Once again, with Nets +155 and 76ers -188:

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As a Nets fan, you can bet $100 for a potential $155 profit and $255 return.

The 76ers backer must bet $188 for a $100 profit and potential $288 return.

Also, bear in mind, The Philadelphia fan will lose $188 if their team, the favorite, gets upset. You will only lose $100 if the Nets, the underdogs, do not win the game. This is why if a team is heavily favored, it’s often not worth the risk for the potential payout.

In summary: betting the team SU is type of ML bet. Your payout is indicated by the “price” represented by a plus or minus sign in the far-right column of the wagering menu.

Betting the over/under

Using our same example, you can see in the middle column of the wagering menu that the expected points total for the game is 234.5. The bet offered here is simple. Do you think the total points scored in this game will be more or less than 234.5?


But, wait! You can’t have a half-point for a game total!

That’s true, but this is the way that sportsbooks can ensure that at least one side wins. Imagine if they had set the points total and 234, and the game finished at exactly 234. No one would win, including the sportsbooks!

In that center box, underneath the points total, you see another one of those triple-digit minus signs. This time, both sides of the bet are offered at -110. This represents Vegas thinks this game could go either way: over or under 234.5. It’s a coin flip, and you have 50/50 odds to win this bet.

But wait, you’re telling me that to win $100, I have to bet $110, no matter which side I choose? Yep, that’s right. That 10% “fee” the sportsbooks charge is called “the vig.” It’s also sometimes called “the juice.” Essentially this is the commission charged by the sportsbook to ensure their business makes some money. If bettors on either side of a bet each have to wager $110 - the sportsbook takes in $220 per pair but only has to pay out the winning side at $210. This ensures them a $10 profit per pair of opposing bets.

So, being a Nets fan, you think Kevin Durant is in line for a huge game, but you know their defense also won’t be able to stop the 76ers. You expect them to win this one with an explosive offense, and you expect a lot of points in this game. You decide to take the over in this game and lay $110 for a potential $100 profit and a total payout of $210. Your college roommate doesn’t feel so optimistic about a high-scoring game. She takes the under on the points total for the same odds. One of you will lose $110, one of you will win $100, and the sportsbook will pocket $10.

In summary: An over/under bet is simply a bet on whether you think the points in a game will be more or less than the listed total. These bets are generally, but not always, offered with a 10% vig and are a 50/50 proposition. Knowing how much “commission” you are paying is key to managing your bankroll, but that’s for our next chapter.

Betting against the spread

Returning to our example, let’s look at the option in the far left of the betting menu. In each box, you see two + and - numbers. The top number is what is called “the spread.” The bottom number may look familiar, as it’s the same rate the sportsbook offered for the over/under bet.


According to this menu, I can take the Brooklyn Nets ATS at +4.5 at the rate of -110.

So, what exactly is “the spread?” Quite simply, the spread is a handicap that puts the two teams on an even playing field. In this case, you can add 4.5 points to the Nets’ final score to determine who wins.

For example: If the final score of the game is Brooklyn 117, Philadelphia 120, as far as the sportsbook is concerned, Brooklyn actually scored 121.5 to Philadelphia’s 120, and Brooklyn wins this game ATS.

Got it? Easy, right?

So, if you bet $110 on the Nets ATS, you would have made a $100 profit for a $210 total payout.

However, if you had bet the Nets on the ML, you could not add the 4.5 handicap, and you would have lost your entire investment.

Now you can see why ML bets are offered at far different rates than O/U and ATS spread bets. If an underdog wins on the ML, the payout is more significant because the outcome was considered less likely. When you bet ATS, there is no underdog as the teams are both handicapped to be even.” The house profits by pocketing “the vig” and hopes to take an even amount of money on both sides of this bet.

There is a thrill in being part of the action, whether you bet the ML, O/U, or ATS. I hope this primer helped make the process a little more accessible. There’s a little skill and a lot of luck involved. Most importantly, remember wagering should always be fun!

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