1. How Do Odds Work Betting
  2. Understanding Odds Ratio In Sports
  3. Understanding Odds In Sports Betting
  4. Sports Betting For Dummies
  5. Understanding Odds In Sports Betting
  6. How To Read Sports Betting Lines

Understanding Sports Odds Identify the type of line you are looking at. All online sports books offer you the chance to have your lines in an 'American' or 'Money line' version. If I were you, I would use this as my standard. An 'American' line uses either a + or - before a number to indicate odds. Welcome to the Sports Betting Odds section of The Sports Geek. If you are new to sports betting and don’t understand how to read betting odds (+150, -110, +2200, etc) we will lay it all out for you and help you learn how the betting odds work.

Understanding how to read odds is crucial to betting on sports. This guide will teach you how to read odds for moneyline, total, and spread bets. We will be looking at American, decimal, and fractional odds, which are three different ways of writing the same odds.

What are Odds?

Odds represent the likelihood of an outcome occurring. In sports betting, each team is assigned odds that represent the likelihood of them winning the game. When the odds for two teams are even, meaning 1 to 1, it means that each team is equally as likely to win the game. If Team A is assigned 2 to 1 odds, it means Team B is twice as likely to win. If Team A is assigned 10 to 1 odds, it means Team B is ten times as likely to win.

Odds are typically expressed with a positive or negative sign in front of them and are not written as 2 to 1 or 3 to 1.

How do Plus and Minus Odds Work?

In a betting line between two teams, the team expected to win, or favorite, will have minus or negative odds. This means for every dollar wagered, you will earn less than a dollar if your bet wins. The team expected to lose, or underdog, will have positive or plus odds. This means for every dollar you wager, you will gain more than a dollar if your bet wins.

The table below shows an NHL game where the Boston Bruins are favorited to beat the St. Louis Blues.

TeamOddsAmount WageredTotal Payout
Boston Bruins-150$1$1.67 ($1 bet + .67 cent won)
Boston Bruins-150$10$16.67 ($10 bet + $6.67 won)
St. Louis Blues+130$1$2.30 ($1 bet + $1.30 won)
St. Louis Blues+130$10$23 ($10 bet + $13 won)

American Odds

American odds are what you will see displayed on almost every sportsbook. Just like the metric system, dates, and miles per hour (mph), Americans do things differently when it comes to betting odds. Take a look at this standard slate of betting odds from for an MLB game.

TeamSpread (Runline)MoneylineTotal
Chicago White Sox+1.5 (-115) +140 Over 9.0 (-120)
Los Angeles Angels-1.5 (-105)-120Under 9 (-105)

The first thing you will notice when reading odds will be that:

  • Odds have either a plus or minus in front of them
  • Odds are in terms of 100

Betting Odds are written in terms of 100 as an industry standard. The easiest way to think of the plus and minus signs is as follows. If it is a plus, you will receive more than a $100 payout on a $100 bet. If it is a minus, you will have to bet more than $100 to win a $100 payout.

How Do Odds Work Betting

Thankfully, you can view your potential winnings on each bet before placing it at an online sportsbook. That said, it is beneficial to understand the betting odds.

Moneyline Bets

Definition of bet: A moneyline bet is a wager on which team will win the game outright. Both the favorite and the underdog are given odds to win the game. Read the chart below to get started on reading odds for the following game:

Green Bay Packers (-150) vs. Detroit Lions (+130)

Moneyline OddsHow to Read itWhat it Means
Lions +130Lions plus 130By betting $100 you will win $130 if the Lions win
Packers -150Packers minus 150To win $100, you must wager $150 on the Packers to win

Spread Bets

Definition of bet: A spread bet is a wager on which team will cover the spread or point spread.

How to read spread odds for the following game: Los Angeles Lakers +5 (-110) vs. Houston Rockets -5 (-110)

Spread OddsHow to Read itWhat it Means
Lakers + 5 (-110)Lakers plus 5 points at minus 110 oddsThe Lakers must win the game, or lose by less than 5 for you to win your bet
Rockets -5 (-110)Rockets minus 5 points at minus 110 oddsThe Rockets must win the game by more than 5 points for you to win your bet. A tie is a push, meaning you don't win or lose.

Total (Over/Under) Bets

Definition of bet: A total bet focuses on how many points are scored, regardless of who wins the game. After a total point score has been set, bettors can wager on whether the actual score of the game will be over or under the set point score.

How to read over/under odds for the following game:

New York Yankees vs. Boston Red Sox Over 7 (-115) Under 7 (-110)

Total OddsHow to Read it
Over 7 (-115)In order to win $100, you must bet $115 on the overall combined run score to be higher than 7
Under 7 (-110)In order to win $100, you must wager $110 on the total combined run score to be less than 7

Keep in mind for both spreads and totals that if the game ends in a draw for the bet (Yankees 4, Red Sox 3), then you get your bet back but do not win or lose any additional money.

Fractional Odds

Understanding Odds Ratio In Sports

Fractional odds are used more commonly in parts of Europe, as well as in horseracing. To calculate fractional odds, you have to do some mental division or enter your desired amount and see what the sportsbook shows as your payout! Here are some odds for a fictitious horse race and how you go about reading them.

Horse NameOddsHow to Read itYour BetYou Win
Laser Focus15/1Fifteen to one$10$150
American Pride7/2Seven to two$10$35 (10 x 3.5)
Green Eggs3/5Three to five$10$6 (10 x .6)

In this race, where we only have three horses, you can see Laser Focus is the underdog, while Green Eggs (no ham) is the favorite. A lot of sportsbooks offer a fractional view if you prefer it to the American odds.

Decimal Odds

Decimals odds are used more commonly in parts of Europe. When using decimal odds, the underdog has the higher of the two numbers, while the favorite has the lower of the two. To calculate decimal odds, you can use the following equation.

Return = Initial Wager x Decimal Value

Example: Let’s say the Arizona Diamondbacks 2.00 are playing the Chicago Cubs 1.90

TeamYour BetYour ReturnYour Profit
Arizona 2.00$1$2$1
Chicago 1.90$10$19.09$9.09

A lot of sportsbooks offer a decimal view if you prefer it to the American odds.

In conclusion, American odds are almost always displayed at any United States sportsbook, while fractional and decimal odds are almost always displayed at any sportsbook outside of the United States. Check out our Guides Page to see where sports betting stands in your state!

Why do Odds Matter in Sports Betting?

The odds are essential when selecting a sportsbook because they affect your money. If you choose a sportsbook with poor odds, you will end up wasting money every time you place a bet. Let’s say you bet $10 on the Vikings moneyline at -200 at one sportsbook. If you win your bet, you pocket $5. If you went line-shopping and found the same bet for -175 at another sportsbook, you would pocket $6, $1 more. Understanding betting odds allows you to decipher between good and bad odds.

Look at the odds below offered on five games from the 2019 NFL Season. Odds from five different sportsbooks are shown. You'll notice each sportsbook offers different odds for each game. If you were betting on these games, you would be able to find the best odds for your desired bets. Using this strategy of line shopping will allow you to save money while betting on games.

How to Use Odds to Calculate Implied Probability

Odds can be used to calculate the implied probability of a team winning or losing a game. You can use a simple math equation to understand what the sportsbook thinks the probability of each team winning is. For positive odds, probability = 100/(odds + 100). For negative odds, probability = odds/(odds – 100).


TeamOddsImplied Odds of WinningImplied Percentage
Miami Heat+130100/(130 + 100) = .434743.47%
Chicago Bulls-110-110/(-110 - 100) = .523852.38%

If you think the Chicago Bulls have a 70% chance of winning, then betting on them would be considered a smart bet.

The process is simple, but If you don’t feel like doing the math, use ESPN’s gamecast preview: preview or Action Network’s odds calculator.

Odds FAQ

Understanding Odds In Sports Betting

What does a negative point spread mean?

In a professional sports matchup a point spread is given to each team for sports betting purposes. When a negative point spread is given to a team, it means they are favorited to win the game. When a positive point spread is given to a team, it means they are not expected to win the game.For example, if the Kansas City Chiefs are minus three (-3) against the Los Angeles Rams (+3), then it is expected that the Kansas City Chiefs will win the game and that Los Angeles will lose.

What do odds of +200 mean?

Odds of +200 mean 2 to 1. For every $1 wagered on a team with +200 odds $2 will be paid out. Odds of +200 are greater are offered on teams that are NOT expected to win a game.

How do parlay odds work?

A parlay bet is a group of spread, moneyline, or total bets combined into one bet to increase the payout odds. In order for the parlay to win, each separate bet has to win. Parlay odds offer bigger payouts than normal odds because they are riskier since each individual bet has to win.

Here is an example of a standard parlay payout table based on true odds. What this means is exact payouts are shown for wagers at -110 odds, where a bet of $110 wins you $100.

Understanding odds ratio in sports

Sports Betting For Dummies


Parlay SizePayouts
2-Team2.645/1
3-Team5.958/1
4-Team12.283/1
5-Team24.359/1
6-Team2.645/1
7-Team91.424/1
8-Team175.446/1
9-Team335.852/1
10-Team642.082/1
11-Team1226.701/1
12-Team2342.793/1

Methodology

For the BettingBuck.com annual best online sportsbooks review published in 2020, a total of 2,300 data points were collected over six months and used to score sportsbooks. Additionally, odds data was collected for each sportsbook on over 1,400 bets to give each sportsbook a comparative odds ranking.

Understanding Odds In Sports Betting

Sports betting sites were scored across seven core categories to computer an overall rating: total number of sports and bets offered, odds, live betting features, mobile apps, educational resources, ease of use, and current bonuses.


How To Read Sports Betting Lines

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