How to Calculate Betting Odds – the Easiest Guide

by GemBet

Before hitting an online casino that offers a vast sports betting section, you must learn how to read betting odds and how you can calculate them. This knowledge is an integral part of each bettor’s arsenal, allowing them to make informed decisions and ultimately seize an opportunity to boost their gains. 

Use this simple guide to collect the most important insights and grasp what you may expect depending on the betting site, market, and selection. See which systems are used and how sports bookmakers influence the final outcome. 

If you want to get more in-depth information and bet on the most anticipated events like a pro, check out more articles in our Sports Odds section. Join our top-ranked betting site to turn these new masteries into real money and claim your welcome offer now! 


The Basic Concept of Sports Betting Odds

Betting odds serve as a guide, showing bettors how much they could win if their predictions come true. Three essential elements go into creating them. The first is the probability, or the likelihood of a particular outcome, while the second is the bookmaker’s share, which ensures they’ll earn regardless of the ultimate result. The final key point you must grasp refers to the drift, determined by the number of people who have bet on either outcome. 

How Do Sports Bookies Set the Odds?

Imagine if you were to flip a coin and bet on the side it would touch down. The chance of it landing on either heads or tails is 50/50. The decimal odds system would present it as 2.00 odds for both outcomes. But if 55% bet on tails and 45% on heads, the bookmaker will lose if it lands on tails. That’s why they’d lower the odds to 1.83 or 1.90, allowing them to keep their share regardless of the bettors’ success. 

There are two other formats bookmakers use to present the odds. American odds use a  “-“ and “+” system, while betting sites in the UK often display fractional odds. 


How to Read Betting Odds & Which Formats Should You Know Of?

The different odds systems don’t change the odds and are used for comprehension only. The format you’d see depends on where you live, but most websites have a built-in setting that lets you swap a particular format for another that works better for you. 

Decimal Odds System (e.g., 2.00)

The decimal odds are used the most in brick-and-mortar establishments and on online betting platforms. This system owes its popularity to being the simplest and allowing slight changes. 

You can calculate decimal odds by subtracting them by 1 to check your future profit. If you bet $1 with 2.00 odds, you’ll win $1, and if the odds are 3.50, your return will be $2.50.  Anything less than 2.00 represents an odds-on bet, so 1.50 odds will let you collect half of your stake. 

Converting decimal odds to a chance of winning relies on the value of the decimal. The betting odds of 2.00 represent a 50% chance of winning, while those above 2.00 show a chance of a win lower than 50%. 

Fractional Odds System (e.g., 2/1)

The fractional odds system is mainly used in the UK and Ireland. It represents the most popular way to present odds in greyhounds or horse racing.

You can convert fractional odds to probability by using this formula, where the odds equal x/y: 

(y / (x + y)) * 100

When translating this odds format to hopefully tangible gains, the second number represents your bet amount while the first depicts your profits. So, if an online casino uses this system in its betting section, know that the odds of 6/1 imply a $1 bet that yields a $6 profit. On the other hand, 2/4 odds means you’d bet $4 only to collect half of your stake. 

Moneyline or American Odds System (e.g., +100/-100)

American odds are used by nearly every online casino and betting site throughout the US. Some call them Moneyline or Vegas odds. They’re based on using a “-“ and “+” system. Think of the “+” as the amount that you win if you bet $100 and the “-“ as the sum you must bet to win $100. 


How to Understand the Probability of Winning a Bet

Probability can be described as a percent of chance of a specific result, normally tied to the listed odds. The formula is no secret – all you have to do is convert the odds into percentages. 

This is where knowing about the popular odds systems comes in handy. While European and Asian bettors mainly know of decimal odds, Americans may have a hard time translating them into their matching format. However, the drill is fairly simple. 

Implied Probability Calculations & Formula

A decimal odd of 1.01 is the same as a 99% chance of winning the bet. In other words – your probability of making a haul is almost absolute! Turning this probability into American odds will state -10,000 odds. You could determine the implied probability from the Moneyline system by using these calculations:

Negative odds: Odds / (Odds +100) * 100

Positive odds: 100 / (Odds +100) * 100 

The implied probability is your best ally when betting because the bookmaker may step over or stay under the pricing lines. It can put you into perspective and help you spot lucrative opportunities seamlessly. 


Why Do Sports Betting Odds Change

To understand why sports odds change, you’ll need to revisit the coin flip example. Bookmakers can play a substantial role in these variations. So, imagine 70% participants betting on heads and 30% on tails. Bookies would face a hurdle if heads win and that’s why the odds would be adjusted to account for such instances.

These adjustments cause the betting odds change in the run-up to an event. If more people bet on Team A than Team B, the odds will shorten for the former and drift for the latter.

Still, if you join a trustworthy betting site, you’re in for a fun and profit-yielding ride. Reputable platforms should greet you with a generous welcome offer and keep feeding you tested insider tips. Sign up to GemBet and kickstart your journey with your deposit back and extra information about how sports betting odds work


The Players’ and Teams’ Stats and Standings Matter – But Everything Can Change at Any Point!

Once you gather the facts and join our legit online casino in Singapore for a successful betting session, remember the essential rule – sports betting is still a game of chance

You may have a vast knowledge of a particular game or profound familiarity with a specific team or player and still run out of luck due to unexpected circumstances. A key performer may get injured right before or during the match, turning the tables and disrupting the odds right in the middle of a live betting session while the event is in full swing. 

Still, the probability of guessing the outcome is always easier if you know the team’s shape and latest results, averages, and players’ forms. These factors will impact your decisions and the prospects of landing a whopping cash prize


Bet on Sports in a Legit Online Casino in Singapore

Understanding how the odds work before placing a bet on a specific sports event is imperative. They’ll show you the likelihood of an outcome, directing you toward skyrocketing your earnings! And while there are three common odds formats sites may display, you can easily convert them into a system you’re familiar with. 

Join our platform and bet pre-match or live with a full HD stream to turn these insights into a massive cash-in! Claim your welcome offer to jump-start a successful betting session, and know we’ll always have your back! If you’re looking for a way to boost your bankroll to a phenomenal size, make sure to take advantage of our 250% Welcome Bonus and enhance your balance with up to SGD 1,000 in bonus money on your first deposits. 

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