How to Understand Odds in Sports Betting Like a Pro

09 / 17 / 2020 By Mark Saldana

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If there’s one thing you know, it’s sports. You’ve been making friendly bets with your buddies for years, and almost always come up a winner. But do you really understand odds in sports betting?

Sports betting odds can be tricky to understand at first, especially since you may see the odds posted in more than one way.

From plus/minus to decimal, to fractional how is anyone supposed to know how to place the best bets?

Don’t sweat it, we’ve got you.

In this guide, we’ll explain everything you need to know about how to understand odds in sports betting, and how you can start creating your own odds.

Understanding Sports Odds: What Are They?

So, you want to place a bet on the upcoming match but you’re not sure how to get started.

First things first, you have to understand the odds to know which bets are worth the risk. We’ll touch more on that in the sections below.

Secondly, you need to know that there are a variety of formats for which odds are displayed, such as:

  • American (plus/minus)
  • Decimal Odds
  • Fractional Odds

All of them are easy to understand, and we’ll show you in the upcoming sections of this article.

Lastly, odds are used to calculate the implied probability of a particular outcome in any sporting event.

Once you have a solid understanding of how the odds work, you’ll be able to determine which bets offer the best payouts and how much money you are willing to wager.

Sports Odds Explained: American Odds

If you don’t know how to calculate sports betting odds, don’t worry, you’re not alone.

The most common type of sports odds used in North America is American Odds, which uses a plus/minus system for calculating payouts.

Below, we’ll answer your question: how are odds calculated in sports?

We’ll start with the American way, and give you some betting odds examples so you know exactly what you’re looking at the next time you want to make a wager.

But first, it’s important to know what odds are designed to do.

  1. Odds flag potential bettors as to the implied probability of the bet
  2. Odds announce the payout you could win if you bet on that outcome

However, odds can be influenced by more than the events that are relevant to the outcome of the game or match.

Many traditional sportsbooks are known for manipulating the odds in their favor and factor in how much the book is charging for you to place your bet. You may hear fellow wagerers refer to this cut as the “juice”, “vig”,  or “cut.”

How Does Plus/Minus Work in Sports Betting?

When you see +130/-240 (or any other three-digit combination) you know you’re dealing with American odds.

The plus or minus indicates whether you’re betting on the favored team or the underdog.

A negative number on the betting line implies the favorite, and exactly how much you have to bet to walk away with a $100 payout.

Positive numbers belong to the underdog, and let you know how much you’ll win if you bet $100.

For example:

American Odds Team Odds  
The Game Vikings -130 Favorite
  Packers +260 Underdog

How Do You Understand Odds in Sports Betting With American Odds?

Using the above example, calculating your odds look like this:

To win $100 on the Vikings (favorites), you would need to wager $130. If you bet $100 on the Packers (underdogs), you’d be paid out $260 in addition to receiving your $100 bet back. 

Calculating Payouts

Let’s say you don’t want to bet $100 of your money — we get it, that can add up. 

Many people prefer to place a series of smaller bets on multiple games to get the most out of the experience. 

Winning two and losing one can be more appealing than losing it all in one shot.

With the above example, let’s calculate the odds of betting the underdog with only $10, instead of $100.

Using the +260 odds on the Packers, a $10 bet would payout $26 in profits, plus the return of your original $10 bet for a total of $36 back in your pocket.

In most cases, the sportsbook you’re betting with will do the calculations before you even place the bet. 

You’ll know the exact payout before you confirm your bet.

Calculating Implied Probability

If you’ve started to research exactly how sports betting works, then you’ve probably heard the term “implied probability”.

The odds are what suggest a particular outcome in any match, and the implied probability refers to the prospect of that outcome.

To calculate the implied probability you need to convert the odds into a percentage.

The reason you’d want to calculate the implied probability is to determine if the estimated probability of a match you wish to bet on is different from the sportsbook so that you can adjust your bet accordingly. 

Remember, that all odds available at a sportsbook include the “juice” or “cut” so you’ll need to factor that in, as the implied probability of every conceivable outcome of a match is going to be above 100%.

This is called overround, and it’s the reason you should remove the “juice” from betting lines before calculating what the oddsmakers actually expect the outcome to be.

how to figure out odds

Sports Odds Explained: Decimal Odds

Of the three types of odds you’ll come across, betting with decimal odds are the easiest to learn.

Decimal style odds are typically used in Europe, but many Sportsbooks default to American odds. However, you should be able to set the preference to any betting style.

Decimal odds look like this:

Decimal Odds Teams Odds Favored
The Match Toronto Blue Jays 2.10 Underdog
  New York Yankees 1.40 Favorite

How Do You Understand Odds in Sports Betting With Decimal Odds?

Calculating your potential winnings with decimal odds is easy. All you have to do is multiply the amount of money you’re wagering with the odds attached to the team you’re betting on.

For example:

Your Bet The Odds Winnings
$30x 1.40 (New York Yankees) = $42
$30x 2.10 (Toronto Blue Jays) = $63


Calculating Implied Probability

Calculating your implied probability is a valuable tool to determine if a wager is worth the risk. 

Using our example above, we’ll determine implied probability using the following formula: 1 / Decimal odds

With the above example, the Toronto Blue Jays implied probability of winning is:

1 / 2.10 = 47.6%

And the New York Yankees implied probability of winning is:

1 / 1.40 = 71.4%

In this case, the New York Yankees have a much higher probability of winning, and therefore the safer bet… unless you know something we don’t. 

Sports Odds Explained: Fractional Odds

Fractional odds are most commonly used in the UK and can typically be seen when placing bets on horse races.

They’re sort of funny looking odds, but when you understand what they mean, they are really easy to calculate.

How Do You Understand Odds in Sports Betting With Fractional Odds?

Let’s say you want to bet on a horse in the Breeders’ Cup Classic. 

You open up your betting app and see strange-looking figures such as 8/3 or 1/2 (which, by the way, we would say “eight to three” or “one to two”).

So, how do you calculate these odds?


The number on the left (8) tells you how many times the oddsmaker expects the related outcome to fail. And the number on the right (3) dictates how many times the outcome should succeed.

So, what does this mean for your pocketbook?

Calculating Payouts

Calculating your payout for fractional betting is really quite easy.

Multiply your bet by the numerator (or top number), then divide the result by the denominator (bottom number). 

For example, if you place a $50 bet on 8/3 odds the calculation would look like this:

(50 x 8) / 3 = $133.33 (a total of $183.33 coming your way).

Or if you placed your $50 bet on the 1/2 odds, then the calculation would look like this:

(50 x 1) / 2 = $25 (for a total of $75 in your pocket).

Calculating Implied Probability

Figuring out the implied probability for fractional bets can be done fairly easily.

Let’s say your horse of choice has 8/3 odds on him, this means that out of 11 races (8+3) your horse is expected to win eight times. Pretty good right?

Now divide the number of times he’s supposed to win by the number of races on the roster and you get your implied probability: 8 / 11 = 72.7%

Remember though, it costs money to play, so anytime you’re calculating odds, whether American, decimal or fractional, the outcomes when added together will always equal more than 100%that’s the “vig” or the “cut” we’ve been talking about.

Men excited about betting

What is a Push?

A push — while not related to odds — can directly affect your payout so we thought it was worth mentioning here.

Being aware of the possibility of a push before you place your first bet on a sports match is important.

So, what is a push, exactly? In simple terms, it’s a tie.

You will not see a push on the moneyline when placing bets, so you need to know in advance if it’s an outcome you can bet on. Typically this only applies if you’re betting against the spread or making a totals bet.

If a push occurs and hasn’t been bet on, then you’ll just get your money back, as it’s considered neither a win nor a loss.

A point spread will usually add half a point to each number so that a push can’t happen, but that’s not always the case, so keep your eye on your bets and all possibilities of a push.

What Is ZenSports? 

Now, that you know how to figure out odds in betting this is where it gets really interesting.

ZenSports is an online peer to peer betting marketplace that removes the need for a bookmaker, and thus the “vig”, “cut”, or “juice”

By eliminating the bookmaker, ZenSports can charge 50-90% lower fees than traditional bookmakers do. 

On top of saving a lot of money, every customer that uses ZenSports is betting against other sports bettors (not greedy bookmakers), so customers feel good knowing that they’re going up against people that are just like them.

Create Your Own Bets and Odds With ZenSports

How does peer to peer betting work, exactly?

By eliminating the bookmaker, ZenSports has essentially created a marketplace for which every bettor plays a role in creating a fun, decentralized ecosystem for everyone involved. 

Here’s a five-step overview of how the ZenSports process currently works:

  1. Makers create bets. Anyone can create any imaginable sports bet they want with their own terms, payout, and wager amount.
  2. Takers accept bets. Anyone can accept part of or a whole bet created by a Maker. 
  3. Makers submit the results of the bet outcome. To prevent a Maker from submitting false results, Makers have an escrow fee of 10% of their bet set aside in case of a dispute by the Taker.
  4. Takers can dispute results. A Taker can dispute any outcome but are required to hold 5% of their bet in escrow aside to prevent the Taker from making false disputes.
  5. The Marketplace resolves disputes. The Marketplace is incentivized to vote correctly because they will receive half of the losing party’s escrow amount if they vote alongside the majority of the voters. The prevailing party received a full refund of their escrow fee, along with half of the losing party’s escrow fee.

All bets are then paid out accordingly.

ZenSports is the only mobile peer to peer sports betting marketplace, where anyone can create and accept bets around the world without the need for a centralized bookmaker.

The future of online sports betting is here.

Download the ZenSports apps