How Betting Odds Works

How Betting Odds Works

Understanding and calculating odds is a technique that everybody who places bets should have. The odds represent your selection’s probability of winning and the amount of money you stand to gain if your bet is successful. At first glance, betting odds might be difficult to comprehend, particularly when they are shown in many formats. However, studying our betting odds explains a guide to assist you in comprehending.

What is the definition of betting odds?

Bookmakers use betting odds to show how likely it is that an event or series of events will happen.

Types of Betting Odds

Fractional/British odds, decimal/European odds, and money line/American odds are the three primary forms of betting odds.

These are only alternative methods of presenting the same item and have no impact on payments. This means that the chances of an event happening (or the percentage chance) can be changed and expressed in any of those three odds types.

How Fractional Odds Are Calculated

Fractional odds (commonly referred to as “British” odds, “UK” odds, or “traditional” odds) are common with British and Irish bookmakers. They are denoted by a slash (/) or a hyphen (-) and are used by most of the world’s top bookies.

A fractional odd of 7/1 (seven-to-one) means that for every dollar placed, you will win $7 in addition to your dollar (the amount you placed). In other words, this is the ratio of the winnings to the original wager, which implies you will get your initial wager ($1) in addition to the profit ($7), for a total payment of $7. Thus, if you wager $10 on 7/1 and win, you will get an overall payment of $80 ($70 profit + $10 bet). 

This is the formula for calculating fractional odds.

Stake + (Stake x (Numerator/Denominator))

Where the numerator and denominator are both odd fractions (e.g., 7/1).

How Decimal Odds Are Calculated

Decimal odds (alternatively referred to as “European” odds) are widely used in continental Europe, Australia, New Zealand, and Canada. On major betting sites, decimals are significantly more common. They offer an alternative to viewing betting odds in fractional form and, in our opinion, are more straightforward to calculate.

The decimal odds value indicates how much one wins for every dollar staked. When dealing with decimal odds, the number indicates the overall payment, not the profit. In other words, your stake is already included in the decimal amount (there is no need to add it back), which simplifies the process of calculating the final payment.

A stake’s total (possible) return is calculated as follows:

 Stake x Decimal Odd Number

Allow us to illustrate this with a few examples.

8.0 is equivalent to 8.0 * £10 stake = £80 total payoff. Profits of £70

5.5 equals 5.5 * £10 stake = £55 total reward. Profits of £45

2.25 is equivalent to 2.25 * £10 stake = £22.50 total payoff. Profits of £12.5

How Money Line Odds Are Calculated.

Money line odds (commonly referred to as “American” or “US” odds) are common in the US. Preferred teams have odds denoted by a negative (-) sign and represent the minimum wager required to win $100. Odds for underdogs, on the other hand, start with a positive (+) symbol and show how much money you get for every $100 you bet.

In both circumstances, winners get a refund of their original stake, which they add to their winnings. The spread between the odds between the preferred and the underdogs becomes wider as the preferred’s chance of winning rises.

Allow us to illustrate with an example:

Assume a bookmaker has set the odds for a certain team (team A) to win at +300. The odds +300 suggest that the bookmaker believes Team A will win the game, although with a considerably lower possibility. You must wager $100 on team A to win $300. If team A wins, you will get a refund of your original $100 wager in addition to the $300 earned, for a total payment of $400.

If the bookmaker gives team A a -500 chance of winning, you must wager $500 to earn $100. If Team A wins, you receive $100, for a total payment of $600 (500 original bets + $100 profit).

Frequently Asked Questions About Betting Odds

Why are decimal odds increasing in popularity as of late?

Historically, bookmakers in the United Kingdom implemented fractional odds, although decimal odds are becoming increasingly prevalent. This could be because it is easier to figure out how much money you could win, or because they are more common in Europe.

Which kind of odds is preferable, decimal or fractional?

When it comes to the odds format, there is no right or wrong. You should just utilize what is more familiar and understandable to you.

What should I do if the odds are provided in decimal and I am used to working with fractions?

Alternatively, you can use an odds converter. However, with the majority of online betting sites, you will be given a choice.

Which is preferable, decimal or fractional odds?

Fractional odds have been used in the United Kingdom for a long time, mostly at racetracks and on the main street.

Decimal odds are more straightforward. The primary difference between the odds is that fractional odds show just gains and do not include the staked amount, while decimal odds do. The migration from fractional to decimal odds was partly precipitated by the rising popularity of betting exchanges 

If the odds vary significantly, it’s quite difficult to adjust the probability without introducing enormous fractions. These are hard for the punter to figure out and are not a good way to show betting odds.

While neither method is superior, there is undeniably a tendency toward preferring decimal odds.


If you’re considering entering the betting industry, it’s necessary to be able to comprehend and analyze various forms of odds. You must be acquainted with the conversions between the various odds formats, the translation of odds to implied probabilities, and the distinctions between actual probabilities and displayed odds. Once all of this is well understood, then you can place an accurate bet that is well calculated and predicted.

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