# How Do Odds Work in Betting?

Learn about American, British, and European Odds Formats

If you are planning to start betting—be it in a casino, sports betting, or any other type—it’s essential to understand the odds. Placing bets intelligently requires having a good grip on the main types of betting odds and the ability to read and interpret their various formats.

The three main types of betting odds are fractional (British) odds, decimal (European) odds, and money line (American) odds. These are alternate ways of presenting the same odds and hold no difference in terms of payouts. This means that the chances (or the percentage probability) of an event occurring can be converted and presented in any of the odds mentioned earlier.

### Key Takeaways

• The three main types of betting odds are fractional (British) odds, decimal (European) odds, and money line (American) odds.
• These types are alternate ways of presenting the same thing and hold no difference in terms of payouts.
• Britsh fractional odds are the ratio of the amount (profit) won to the stake.
• European decimal odds represent the amount one wins for every $1 wagered. • Depending on the negative or positive sign, American money line odds either indicate the amount one needs to wager to win$100 or the amount one would win for every $100 staked. ## How British/Fractional Odds Work Fractional odds (aka “British” odds, “U.K.” odds, or “traditional” odds) are popular among British and Irish bookies. They are typically written with a slash (/) or hyphen (-). A fractional listing of 6/1 (six-to-one) odds would mean that you win$6 against every $1 you wager and receive your dollar back (i.e., the amount you wagered). In other words, this is the ratio of the amount (profit) won to the initial bet, which means that you will receive your stake ($1) in addition to the profit ($6), resulting in a total payout of$7. Therefore, if you stake $10 at 6/1 and win, you get a total payout of$70 ($60 profit +$10 stake).

The total (potential) return on a stake can be stated as:

Tp = ( S ( N / D ) ) + S

Where:

• Tp is the total payout
• S is Stake
• N/D is the numerator/denominator of the fractional odd (e.g., 28/6)

Let’s posit that the following are the odds on the three teams most likely to win the 2022 NBA Championship:

• Brooklyn Nets: 13/5
• Golden State Warriors: 9/2
• Milwaukee Bucks: 7/1

It can quickly be determined that the Brooklyn Nets are the favorites, while the odds on Golden State and Milwaukee winning are longer. You would win $13 against every$5 you wager on Brooklyn to be the champions. Meanwhile, you'd win $9 against each$2 you put at stake for Golden State to win, which is a bit less probable. For Milwaukee, you'd win $7 against each$1 bet.

In the above example, if you bet $100 on Brooklyn to win, you could make a$260 profit ($100 x (13/5)) and get back your initial stake of$100, resulting in a total payout of $360. However, if you wager$100 on Golden State to win, you could receive a profit of $450 ($100 x (9/2)) in addition to the $100 initial stake, leading to a total payout of$550.

The potential profit for a Milwaukee win would be even higher because you could make a profit of $700 ($100 x (7/1)). With the initial stake of $100 returned, it would result in a total payout of$800.

## How European/Decimal Odds Work

Decimal odds (aka “European” odds, “digital” odds, or “continental” odds) are popular in continental Europe, Australia, New Zealand, and Canada. These are a bit easier to work with and understand. The favorites and underdogs can be spotted instantaneously by looking at the numbers.

The decimal odds number represents the amount one wins for every $1 wagered. For decimal odds, the number represents the total payout rather than the profit. In other words, your stake is already included in the decimal number (no need to add back your stake), which makes its total payout calculation easier. The total (potential) return on a stake can be calculated as: Tp = S * D Where: • Tp is the total profit • S is Stake • D is the decimal odd Let’s look at an example involving who might have won the 2020 U.S. presidential election. • Donald Trump: 4.00 • Joe Biden: 1.3 These numbers represent the amount you could win against each$1 you put at stake. So, if you bet $100 on Donald Trump to be reelected as president, you could receive a total payout of$400 ($100 x 4.00). This amount includes the initial stake of$100, resulting in a net profit of $300. Similarly, you could receive a total payout of$130 ($100 x 1.3) if you successfully bet$100 on Joe Biden. Deducting $100 from this return gives you the$30 net profit earned.

Here we can see that the bookmaker correctly priced Biden as the favorite to win the election. The higher the total payout (i.e., the higher the decimal odd), the less probable (and riskier) it is for the listed candidate to win.

## How American/Money Line Odds Work

Money line odds (aka “American” odds or “U.S.” odds) are popular in the United States. The odds for favorites are accompanied by a minus (-) sign and indicate the amount you need to stake to win $100. On the other hand, the odds for the underdogs are accompanied by a positive (+) sign and indicate the amount won for every$100 staked.

In 2018 the Supreme Court gave U.S. states permission to legalize sports betting if they wish to do so. It is legal in 30 states, with other states either working on legislation or not considering it.

In both cases, winners get their initial wager back in addition to the amount won. The difference between the odds for the favorite and the underdog widens as the probability of winning for the favorite increases.

Let’s understand this with the help of an example:

Let’s say a betting website priced an NFL game between the Pittsburgh Steelers and the Kansas City Chiefs with the following money line odds.

• Steelers: +585
• Chiefs: -760

## What Are Vegas Odds?

Vegas odds are used in sportsbooks. American money lines are used and include a point spread and total number of points the bookmaker thinks will be scored. This allows bettors to bet over or under the bookmaker's score, and indicate what they believe the difference in points will be.

## The Bottom Line

If you are planning to enter the betting world, it is important to be able to understand and interpret all types of odds well. You need to be familiar with the conversions between the different formats of odds, the conversion of odds into implied probabilities, and the differences between the true chances of an outcome, as well as the odds on display. Only then can you place a well-educated bet.

If you or someone you know has a gambling disorder, please call the National Problem Gambling Helpline at 1-800-522-4700, or visit ncpgambling.org/chat to chat with a helpline specialist.

Article Sources
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1. American Gaming Association. "Interactive Map: Sports Betting in the U.S."

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