How To Use Percentages Instead of Odds in Online Gambling

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BetMGM Sep 26, 2021, 5:03 PM

Odds are the bedrock of gambling. They provide the information you need to determine the chances of your wager succeeding or failing. They also help you to calculate how much you will win if your bet succeeds. If you understand the odds, you have a much better chance of developing a good strategy for sports betting or casino games. But odds can be tricky to work with. They tell you how much money you can win or lose, but they don’t clearly tell you what your chances are of winning the bet. 

That’s why many players convert their betting odds to percentages and make betting decisions based on those numbers. If you know the percentage probability of success or failure, it’s much easier to make an informed choice when playing casino table games and online slots. This blog looks at how to convert odds to percentages and apply them to any online casino situation. Read on for more.

Understanding Odds vs. Probability in Gambling

Probability and odds are closely related concepts in the world of gambling and statistics, but they represent information differently and are often used in distinct ways.

Probability is the term used to describe how likely a particular event or outcome is to happen. It plays a fundamental role in all forms of gambling, from casino games to sports betting and even lotteries. It’s expressed as a value between 0 (impossible) and 1 (certain). For example, the probability of flipping a coin and getting heads is 0.5 (or 50%).

Odds, on the other hand, represent the comparison between the likelihood of an event happening and the likelihood of it not happening. They are often expressed as a ratio or a fraction. If the probability of an event is 0.5, the odds in favor of the event are 1 to 1, which means it’s equally likely to happen as not.

When working with these mathematical concepts, it’s important to understand that probability serves as the foundation upon which odds are built. First, you calculate the probability of an event transpiring, and then you can move on to calculate the odds based on this probability. 

Betting Odds Explained

So, how do betting odds work? Odds are ratios of your chances of losing against your chances of winning. They can be expressed as fractions, decimals, or moneyline odds (American odds).

The fractional odds for a coin toss are 1/1, which means you have the same chance of winning as you do of losing. That’s simple enough, but things can get complicated quite quickly. Let’s take a simple example. If you own 1 of 4 tickets, you have a 1 in 4 chance to win, but your odds are 3/1. How sure would you feel about betting on a horse with odds of 4:3? What about a horse with odds of 1/3? It isn’t obvious that the probability of this bet succeeding is 75%.

It’s even less obvious when working with American and decimal odds. Odds of 1/3 convert to American odds of -300. That means you have to put down $300 to win $100. This shows that our hypothetical horse is a favorite, but it’s not much help if you’re trying to work out the actual percentage probability of a win.

How to Convert Fractional Odds to a Percentage

If you’re looking to work with percentages instead of odds, the good news is that it’s easy to convert from one to another. All you need to do to see your betting odds as a percentage is apply a mathematical formula. It’s simple enough to do on a calculator.

Here’s how to convert fractional odds to figure out the probability of a win. First, add the numbers on each side of the fraction together. Divide 1 by the result and multiply by 100. Let’s do that with odds of 3/1. Add 3 + 1 to get 4. Divide 1 by 4 to get 0.25. Multiply 0.25 by 100 to get 25. The probability of a win is 25%.

How to Convert American Odds to a Percentage

The method of converting American odds to percentages depends on whether you have positive (underdog) or negative (favorite) odds. Positive odds show how much you’ll win on a bet of $100. Negative odds show how much you need to wager to make $100.

To convert positive odds into percentages, divide 100 by the odds + 100 and multiply the result by 100. For odds of 300, divide 100 by 400 to get 0.25 and multiply that by 100 to get 25%.

For negative odds, you divide the odds by the odds +100 and multiply by 100. Let’s work with odds of -300. Divide 300 by 400 and multiply by 100. The result is a 75% probability of a win.

How to Convert Decimal Odds to a Percentage

Decimal odds come in decimal form (1.80, 3.50, 6.40, and so on). They’re also geared more to payouts than probabilities. To calculate how much a winning bet will pay, simply multiply it by your bet. Put $100 on a bet with decimal odds of 1.50, and you’ll get $150 if you win.

To work out your chances of winning from decimal odds, simply divide 100 by the odds. So, decimal odds of 1,50 would yield an impressive winning probability of 66.67%! If you’ve got decimal odds of 10, your chances to win are exactly 10%.

The alternative to calculating percentages yourself is to use an online odds converter. You could even put together an odds-to-percentage chart and keep that nearby so that you don’t need to go and do the calculations every time you want to convert odds to a percentage. 

Playing With Percentages

Using percentages is very useful in sports betting, but it can also help with online casino games. The most important percentage to keep in mind is the house edge. That’s the average amount of money the casino makes on a particular game over a certain number of plays, usually in the millions. Some games tell you straight up what the house edge is. 

Real online slots all come with an RTP (return to player) percentage. That’s the money the game gives back on average. Flip it around, and you get the house edge. Asgardian Stones, for example, has an RTP of 96.1%, so the house edge is 3.99%. Gonzo’s Quest has an RTP of 95.97%, so the house edge is slightly more.

Dig a little deeper, and you’ll find that as much fun as online slots can be, they’re not the casino games with the best odds. That honor goes to casino table games. For instance, the house edge on the banker’s hand in baccarat is 1.06%, while it’s 2.7% for an even money bet on French Roulette, and it can go as low as half a percent for blackjack and video poker. But the best online casino bet in the house has to be “craps odds.” It’s the only bet where there’s no house edge at all.

Of course, recreational gambling is all about enjoying yourself, and sometimes, it’s more fun to take a chance on a riskier bet than to always play it safe. But it always helps to know the percentage probability of winning when you’re playing at an online casino for real money. Your betting decisions will improve, and your bankroll will last longer, so you’ll have a better time.

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Our BetMGM editors and authors are casino experts with a wealth of knowledge of the online casino industry at all levels. Their coverage includes company news, game reviews, how-to instructional articles, strategy guides, and editorials showcasing BetMGM’s superior product and game library.

Our BetMGM editors and authors are casino experts with a wealth of knowledge of the online casino industry at all levels. Their coverage includes company news, game reviews, how-to instructional articles, strategy guides, and editorials showcasing BetMGM’s superior product and game library.