Post Action Betting

How to read and calculate sports betting odds

How do sports betting odds work
How do sports betting odds work
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Betting odds have always lined newspapers, and now they’ve started to become popularized in electronic applications, too, as the presence of mobile betting expands. Some formats of betting odds are different by country or by sport, and it’s important to have those betting odds explained so the best way to maximize money is understood.

But before you place your next bet, it’s important to understand how betting odds work and how to read them — regardless of whether you wager online or in-person. The Post answers questions below that’ll help you accomplish that. 

How to read sports betting odds

Betting odds can be displayed in three distinct formats — American, decimal and fractional — and they signal a probability of the game, or teams, they’re connected to and how much an individual could win by selecting those odds. 

For American odds, which are the default options at United States sportsbooks according to Action Network, there’s a “+” or “-” symbol in front of a three-digit number.

For decimal odds, there’s a number rounded to two decimal places, like New York Yankees (5.40), that determines the amount that you wager is multiplied by to determine the winnings.

And for fractional odds, which are perhaps most commonly seen during horse races, the numerator details the number of times the bookkeeper expects the result to fail while the denominator illustrates the number of times they expect the result to succeed. If it’s 8/5 odds for a race for Horse A against Horse B, that means Horse would be expected to lose eight out of the 13 outcomes while winning the other five.

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What do the + and – mean in sports betting?

With bets, they can be placed on either the favorite, known as the team projected to win, or the underdog, which is the team that’s predicted to lose. The “+” sign in front of a number — for example, +350 — means that a bet has been placed on the underdog, and the three digits following that sign indicate the amount paid out if the bet wins and the bettor had wagered $100.

The “-” sign in front of a number indicates that a bet has been placed on the favorite, and the three digits that follow, similar to the bets on the underdog, signal how much someone would make if they bet $100.

How do bookmakers create odds?

The important factor to remember about bookmakers and odds they create is that everything happens with the central goal of making a profit in mind. If every possible bet that people could wager on is covered, the hope would be that the books eventually balance out between who won and who lost their bets. Odds are heavily influenced by statistical and analytical research too, considering past outcomes given certain opponents and situations.

How to calculate payouts of odds bets

For American odds, since outcomes are calculated based on a $100 bet. If, for example, the New York Giants are favored in their matchup against the Philadelphia Eagles with a -120 line, and someone were to bet $24, their payout is calculated when the 24 is multiplied by the $100 baseline bet and then divided by 120. This payout would be $20.

In bets for the underdog, though, the fraction is flipped. If the Giants were underdogs against the Eagles, with the line +120, that 120 would be multiplied by 24 and divided by 100 — giving a payout of $28.80.

The method for calculating winnings for decimal and fractional odds is slightly different, though. If, given the Yankees example above, $50 is wagered on the 5.40 odds and the bet win, those two numbers multiplied together minus the original wager payment determines the winnings. In this example, that total is $220.

And for fractional odds, those winnings are calculated by taking the wagered amount and multiplying it by the fraction. If $25 was wagered for the horse racing example, the total winnings would be $40.