The Basics of Sports Betting Odds: + And – In Sports Betting

Sports Betting Odds: What You Need to Know
- Types of Betting Odds: Familiarize yourself with various types of odds in sports betting, like fractional, decimal, and American (moneyline) odds.
- Reading Odds: Learn how to read and interpret these different types of odds to understand the potential payout of a wager.
- Calculating Probabilities: Understand how odds represent implied probabilities of an event’s outcome and how to calculate these probabilities from given odds.
- Use of Odds in Bets: When placing bets, recognize how odds can determine whether a bet could be profitable, requiring a balance between perceived risk and potential reward.
- Advanced Odds Knowledge: Explore how sportsbooks set odds and how odds can shift based on betting patterns, which can be utilized for strategic betting.
Sports betting odds are the foundation of wagering. They can provide key insights into the likelihood of an outcome and, more importantly, allow you to calculate the money you’ll receive for a winning bet.
There are three main formats for displaying odds: American, decimal, and fractional. Each format conveys the same information but in different ways.
American odds show your profit in relation to $100 bets, decimal odds show a simple multiplier for your stake, and fractional odds present your potential winnings as a fraction.
This page focuses on American sports betting odds, breaking down how they work to help bettors understand and utilize them effectively.
We’ll cover the basics of the odds structure, explain the rest of the standard odds formats, show you how to distinguish between underdogs and favorites, and give you some tips for honing your betting strategy.
What do the + and – Signs Mean?
In American odds, one of the first things you’ll notice will be a plus or minus sign in front of a number. Positive odds indicate the amount you’ll win on a $100 bet, and negative odds indicate the amount you’ll need to wager to win $100 on a bet.

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Distinguishing Between Favorites and Underdogs
Favorites and underdogs are usually indicated by a plus or minus sign ahead in American odds, although this is not always true.
For example, if the Dallas Cowboys are listed at -150 to win a game on the money line, and the Arizona Cardinals are +175, then Dallas is considered the favorite.
Another example would be futures markets. If the Boston Bruins are priced at -110 to win the Stanley Cup, and the Vegas Golden Knights are priced at +300, the Bruins are the favorites.
Despite this, positive and negative odds do not always tell you who is favorite and underdog. Sometimes, several outcomes in a wager will have negative odds or positive odds.
In this case, the larger number is the favorite for negative odds, and for positive odds, the smaller number is the favorite.
How American Sports Betting Odds Work
American odds revolve around $100 wagers and positive or negative odds to indicate a potential profit or required stake, respectively.
For example, if you bet on the Los Angeles Lakers priced at +200 odds, a $100 bet would return $300: your $100 stake and $200 profit.
If you bet on the Philadelphia Flyers at -200 and staked $200, it would return $300: your $200 stake plus $100 profit. American odds emphasize probability and risk differently from other standard odds formats, like fractional or decimal odds.
Understanding Implied Probability
Implied probability is the percentage chance of an event as determined solely by the odds provided by your sportsbook or sports betting apps and change depending on the bets, such as moneyline odds.
Understanding this allows you to compare how likely the betting companies believe an outcome to be and compare this likelihood to your own analysis.
For American odds, use this formula to calculate the implied probability:
● For negative odds: Odds / (Odds + 100) * 100
● For positive odds: 100 / (Odds + 100) * 100
For example, if the Sacramento Kings are +300 to win the Pacific Division, you would calculate 100 / (300+100) * 100. This would mean your sportsbook considers the Kings to have a 25% chance of finishing first in the Pacific Division.
If the Los Angeles Clippers are -110, you would calculate 110 / (110+100) * 100, meaning they would have a 52% chance of winning the division.
Other odds formats have different formulas to discover implied probability. For example, you would calculate 100 / ((Numerator / Denominator) + 1) for fractional odds. For decimal odds, you divide 100 by your odds.
Calculating Potential Payouts
Calculating potential payouts from American odds depends on whether your odds are positive or negative.
For example, if you bet $50 on the Kansas City Chiefs to win the AFC West at -200, you could work out the decimal odds by dividing 100 by the odds and adding 1 to get 1.5.
Multiply this number by your stake of $50, and you will work out that you get a total payout of $75, $25 in profit, and your $50 stake.
For positive odds, simply divide the odds by 100 and add 1. For example, if you bet $100 on Detroit Tigers to win the World Series at +300, divide 300/100 to get 3, add 1 to get 4 and multiply by your stake to get your return, $400. Remember, that return includes your $100 bet, so your profit is $300.

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Types of Sports Betting Odds
Betting odds come in three main formats: American, decimal, and fractional. Each format shows the same odds, just with a different emphasis, and each expresses your potential return slightly differently.
No odds format is more profitable than the other. Each shows the same thing. Understanding the different types of odds format is crucial, so we’ve given an overview of the main formats below.
American Odds
American odds are usually the default odds format at US sportsbooks. These odds revolve around $100 bets, with favorites indicated by a minus sign and underdogs indicated by a plus sign.
For positive odds, the number represents the profit on a $100 bet. For negative odds, the number represents the amount you would have to wager to get a $100 profit.
Decimal Odds
Decimal odds are quite simple to understand – they represent the payout for every $1 wagered. For example, if you wager $100 on LAFC to win the MLS Cup at 16.00, simply multiply your stake by the decimal odds.
This means if your wager was successful, it’ll return $1,600, including your $100 stake. Decimal odds are more common at European sportsbooks but can be pretty valuable for three-way markets and are preferred by some bettors as they are simple to understand.
Fractional Odds
Fractional odds are another standard sports betting format at US sportsbooks that present odds as a fraction, such as 7/1 or 10/3. The numerator (first number) represents the potential profit, whereas the denominator (second number) represents the stake required to achieve that profit.
For instance, a $20 bet on the New York Jets to win the AFC East at 7/2 odds would return $90 in total – your $20 stake plus $70 profit. Similarly, a $15 wager on the Colorado Avalanche to win the Stanley Cup at 10/3 odds would return $65 – your $15 stake plus $50 profit.
To work out your profit, simply multiply your stake by the numerator and divide by the denominator.
Key Concepts in Sports Betting
Understanding key betting concepts is essential for sports bettors to hone their strategy effectively. From learning types of bets to understanding sportsbook commissions, getting to know these foundational aspects of sports betting is pivotal.
Below, we’ve explored a few key elements of using an online sportsbook.
Understanding Point Spreads
Points spreads are a market offered at several of the best US sportsbooks. A spread bet is a wager on the margin of victory rather than the outcome.
Usually provided for football and basketball markets, your sportsbook will designate a favorite and assign a betting line. This betting line is the required margin of victory for a wager on the favorite to pay out.
For example, for a game between the Dallas Cowboys and the San Francisco 49ers, if your sportsbook has the Cowboys as the favorite with a betting line of 3.5, this will be displayed as Dallas Cowboys (-3.5) on your bet slip.
For your bet to payout, Dallas must win by more than a field goal. If San Francisco wins or Dallas wins by three points or under, your bet would settle for a loss.
Sportsbooks, like the FanDuel Sportsbooks, usually provide spreads in increments of 0.5, known as the hook, to prevent exact matches.
However, sometimes, retail sportsbook may offer a whole number spread. If you wager on this and the margin of victory is the same as the spread, the sportsbook will settle your bet as a push and return your stake.

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What Are Moneylines?
A moneyline bets is a simple type of wager compared to a point spread because it is a sports betting market depending solely on the outcome of an event. Bettors can win a moneyline bet just by picking the winner in a sporting event.
For example, a sports bettor would win a moneyline if they can successfully pick the winner of a soccer match between Minnesota United and Austin FC.
The Role of Vig or Juice in Betting
The vig, or vigorish, is a commission applied to odds to ensure that sportsbooks make a profit regardless of a sporting event’s outcome. The fee is embedded in the odds, meaning the favorite often has smaller odds than if a two-way market was mathematically split.
The best way to demonstrate this is with a hypothetical football game between Columbus Blue Jackets and New York Islanders in the NHL, two evenly matched teams. Sportsbooks rated both teams as having an equal chance of victory. So, in theory, both teams’ odds would be +100.
However, sportsbooks will offer -110 for each team instead, meaning you’ll have to wager $110 to win $100. This $10 difference represents the vig and helps sportsbooks manage risk.
To reduce the impact of vig, sports bettors should compare odds across several online sportsbooks to see the best value in the market.
Strategies for Successful Betting
Building a successful betting strategy requires more than just luck. It demands effort, research, discipline, and the ability to determine value.
Below, we’ve explored some elements you can add to your wagering game to make informed decisions and improve your long-term betting fortunes.
Importance of Research and Analysis
While a significant amount of success in betting stems from luck, researching and analyzing patterns in sports can increase the chances of picking a successful wager.
In the modern era, plenty of sources offer statistics and data to give you an insight into sporting events and help you find value in the market.
Check out trusted sources for sports data to analyze the market alongside the odds provided by your sportsbook. When you examine the player or team data, see whether sportsbooks or your fellow bettors might have missed any trends.
For example, if the fundamental statistics point to an NFL team underperforming despite winning, you could wager on the team to lose the next game. By doing this, you’ll be able to identify value in the market and potentially increase your returns.
Managing your Bankroll
Effective bankroll management is essential for executing a successful betting strategy. Start by determining your betting budget, and always ensure you don’t bet more than you can lose.
Decide on your wagers after researching and analyzing data, and depending on your confidence in each wager, decide on a stake for each. Doing this mathematically and analytically prevents you from placing emotional impulse bets.
Avoid chasing losses by increasing your stake irrationally, stick to consistency wagers, and maintain discipline – even during a losing streak. Take breaks and re-analyze the data if you feel your strategy isn’t working, and track your bets to give you insights into your performance over time.
Maintaining strict discipline over your bankroll can improve your chances of success, and learn from your mistakes over time.

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Recognizing Value Bets
One thing to know when starting in betting is that sportsbooks aren’t perfect, and odds aren’t a statistical guarantee of the likelihood of an outcome.
Sometimes, you can find value in the market that sportsbooks and your fellow bettors can’t see. To find value in the market, check out a range of data sources and look for patterns starting to emerge or related stats with hidden potential future outcomes.
For example, if you’re betting on soccer, a team that has a high number of yellow cards and fouls but not red cards might be undervalued for a red card in its next match, as it has not had many red cards but looks likely to receive one in the future. Insights like these can help you boost your profitability.
Common Misconceptions about Sports Betting Odds
Understanding betting odds and trends is crucial for making informed wagers. Many novice bettors misinterpret odds and use short-term trends and odds movement as signs of increasing likelihood in probabilities. Below, we’ve provided advice for new bettors to avoid common pitfalls.
Odds as a Guarantee of Winning
A common mistake made by novice bettors is believing that odds guarantee an outcome. Sportsbooks do not have a crystal ball and are playing a game alongside bettors. While sportsbooks have access to several insights, several factors, including betting volume, affect the price set.
Betting Trends Vs. Statistical Analysis
Many bettors mistake trends for reliable indicators of future performance. Past performances are not always a good indicator of future form. Similarly, a ‘hot hand’ from a player in basketball can see a flurry of wagers from bettors convinced that a player will continue to score at a high rate, even though streaks always end.
Sportsbooks know this and will shorten odds for players and teams in good form to attract bets, even though the form is about to end. Bettors with the best strategies focus on data rather than surface-level patterns and identify accurate probabilities through statistical analysis.
With a data-driven approach, you can improve your betting strategy.
Frequently Asked Questions
What do the + and – Mean in Sports Betting?
In American Odds, a + sign generally indicates an underdog in the betting. The plus sign shows the profit you’ll receive for a $100 wager on the outcome. A – sign generally indicates a favorite, and the negative figure indicates the amount you’ll need to wager to receive $100 in profit.
How do Sports Betting odds Change?
Odds change on various factors, including team form, weather, injuries, historical matchups, and player availability. You’ll notice that the odds will shorten and lengthen depending on new information and updates in the lead-up to an event. Odds will also change depending on betting volume.
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