They’re displayed as a fraction (such as 5/1 or 1/2), and show bettors how much they’ll win relative to their stake. Fractional odds—also known as UK odds—are commonly used in the United Kingdom and by some US-facing sportsbooks. Let’s break this down again with a smaller — $5 wager to show the simplicity of decimal odds. The lower the decimal, the more likely the sportsbook thinks that team is going to win, and the less you’ll earn for betting on them.
If you’re still mastering how to read betting odds — using a betting calculator is a smart move. Failing to account for vig when evaluating betting probability leads to false conclusions about value when learning how to read betting odds. If two evenly matched teams both have odds of -110, each implies a 52.4% win chance, adding to 104.8%. Implied probability is the true likelihood a sportsbook is assigning to an outcome based on the odds.
If your bet is successful, a +125 implies that a £100 wager yields a profit of £125 (equivalent to 5/4 in fractional odds and 2.25 in decimal odds). Meanwhile, odds of +200 suggest that betting £100 results in a £200 profit upon winning (equivalent to 2/1 in fractional and 3.0 in decimal odds). If the odds are 2.25, betting £1 will grant you a total of £2.25 if successful (equivalent to 5/4 in fractional odds and +125 in moneyline odds).
Keep Learning
But if the fractions are confusing, many US sportsbooks allow you to switch odds formats in your account settings. Let’s go back to the Buffalo Bills vs Baltimore Ravens — but now view it through the lens of fractional odds. These odds are often used in horse racing and soccer, but you may also find them offered on big US games.
For point spread bets (which are most popular in football and basketball), one team will generally be favored by a certain number of points over the opponent. There are also exotic wagers such as exacta (top two horses in the exact order), trifecta (top three horses in the exact order) and superfecta (top four horses in the exact order). The most common wagers in golf betting are tournament winner (top-five finish), top-10 finish, top-20 finish and first-round leader.
What are the different types of betting odds?
Sportsbooks set these prices from statistical models (team data), injury news and, crucially, how money best value bets today is coming in. So, learning how to read betting odds is essential. Teams then have to issue their final injury report 90 minutes before kickoff — which lists which players are inactive. If a key player is ruled out due to injury, that can significantly impact the odds of a game, turning an underdog into a favorite and vice versa.
You’re fairly unlikely to need to do much converting most of the time — as most betting sites allow you to choose your preferred format of odds in your account settings. To start with — they come in two different formats, depending on the likelihood of an outcome. The only trouble with fractional odds is that it can be quite difficult to compare them — especially if you’re not yet very comfortable with reading them. Convert to implied probability (53.49% vs 52.38%) or decimal (1.8696 vs 1.9091). Multiply decimal odds for each leg to estimate “fair” payout — then compare to the book’s offer. Once you can convert between formats, you’ll understand prices, compare books, and spot value faster.
Implied odds
There are also props for total touchdowns, the number of 3-pointers a player will make, how many points a hockey player will record in a game and more. Prop bets are wagers on specific instances occurring in a game. Winning a bet on the Trailblazers at +2.5 would require that team to lose by one or two points or win the game outright. If the game appears to be a mismatch, one team will have much shorter odds than the other in order to reflect their perceived advantage. Here’s a breakdown of different types of bets that can be made at top sportsbooks. A fractional listing may be written as 4/1 (which means a bettor would win $4 for every $1 wagered), signifying a bet on an underdog.
A different representation of the same sports betting odds can be found in fractional odds, which present them in a fraction format. For instance, odds for each of the Final Four teams’ chances of winning the national championship are posted by sportsbooks during the NCAA men’s basketball tournament. Among sportsbooks in the United States, this betting odds format is the most prevalent.
Each sportsbook odds format—whether American odds (decimal odds), or fractional odds—presents the same core information in a different way. Most online sportsbooks still follow Vegas-style lines, especially in American odds format. You may determine if a team is the favorite or the underdog by looking for the + and – signs. Additionally, a lot of online sportsbooks allow you to change your settings between American, decimal, and fractional odds. With fractional odds, it’s all about how much you need to bet to earn back a return. Simply glance at the number to determine which team is the favorite without using plus or minus signs.
An Explanation of American Odds
Profitability over time is mathematically quantified by expected value. Bettors tend to overestimate longshots and underestimate favorites, particularly in low-payout markets like futures—this phenomenon is known as the favorite–longshot bias. Advanced players apply tools or formulas to adjust for vig, allowing them to determine the “real” odds. By adjusting for the margin, one can normalize prices and derive the true expected value.
The sportsbook responds to various factors such as form (injuries), weather, head-to-head results, and even the actions of bettors themselves, causing odds to fluctuate. A plus (+) sign signifies the team as the underdog; if they win — your earnings will exceed your initial investment. A higher wager is required to win $100 if the team is favored. By placing an Over/Under bet, you predict the total points scored in the game rather than selecting a specific team. Here are the types of bets most frequently encountered by both novice and seasoned bettors.