Knowing how to read betting odds helps you quickly determine whether a wager is actually worth placing. The odds tell you how much a bet pays and how likely it is to win, so they let you size up any market in seconds.
This guide breaks down decimal, fractional, and American odds at crypto sportsbooks. We’ll explain how to convert between them, and we’ll discuss the implied probability and sportsbook margin hidden in every price.
What Betting Odds Actually Represent
Betting odds provide two key pieces of information:
- How much you stand to win if the bet succeeds.
- The implied probability of the bet winning.
When you know how to read betting odds, you can quickly determine whether any bet is worth placing. Just weigh the potential return against how likely you think the outcome really is. If the reward justifies the risk, place the bet. If not, walk away.
Decimal Odds
Most crypto sportsbooks display their odds in the decimal format. You can easily switch to fractional odds or American odds if you prefer, but the decimal format tends to be the default.
It’s easy to see why, as this is the most beginner-friendly format. Decimal odds tell you the total return you’d get from a winning bet. The total return includes your profit, plus the return of your original stake (you always get your stake back on winning bets).
Here’s an example of decimal odds:
- New York Knicks to beat Miami Heat (1.75)
- Miami Heat to beat New York Knicks (2.10)
You simply multiply your stake (bet amount) by the odds to work out your return. For example, a $10 bet on the Knicks would return $17.50, while a $100 bet on the Knicks would return $175.
Fractional Odds
Fractional odds are popular in certain countries, including the UK and Ireland. This also tends to be the default format for horse racing.
They tell you the profit you’d earn from a winning bet, rather than the total return. Here’s the same example, but in the fractional format:
- New York Knicks to beat Miami Heat (3/4)
- Miami Heat to beat New York Knicks (11/10)
You can multiply your stake by the fractional odds to work out your potential profit. For instance, a $10 bet on the Knicks at 3/4 would deliver a $7.50 profit. You’d get your $10 stake back, so your total return would be $17.50.
Meanwhile, a $10 bet on the Heat would provide an $11 profit. Your total return would be $21. The larger potential profit available on the Heat tells you that they’re the underdogs.
If you’re thinking about decimal vs. fractional odds, the main difference is that decimal odds tell you the total return, whereas fractional odds highlight your potential profit.
American Odds
This is the most common odds format in the United States. American odds can either be positive or negative. Here’s that same example once again, but in the American format:
- New York Knicks to beat Miami Heat (-133)
- Miami Heat to beat New York Knicks (+110)
If the odds are negative, they tell you how much you’d need to stake to earn a $100 profit. A $133 bet on the Knicks would deliver a $100 profit.
When the odds are positive, they highlight the profit you’d earn from a $100 bet. In this example, a $100 bet on the Heat would earn you a $110 profit.
The numbers are just a guideline. You don’t need to bet $100, as you can choose your preferred stake. For example, a $10 bet on the Heat would earn you an $11 profit, whereas a $200 wager would deliver a $220 profit.
Converting Between Odds Formats
Converting between the three formats is straightforward. The easiest approach is to treat decimal odds as your hub, as every other format converts cleanly to and from the decimal format.
- Fractional to decimal odds: divide the top number (numerator) by the bottom number (denominator) and then add 1 (3/4 becomes 0.75 + 1 = 1.75).
- Decimal to fractional odds: subtract 1 and then express the result as a fraction (1.75 becomes 0.75, or 3/4).
- Decimal to American: if the odds are 2.00 or higher, subtract 1 and multiply by 100 for a positive figure (2.50 becomes +150). If they are below 2.00, divide -100 by the decimal odds minus 1 (1.50 becomes -200).
- American to decimal: for positive odds, divide by 100 and add 1 (+150 becomes 2.50). For negative odds, divide 100 by the odds (ignoring the minus sign) and add 1 (-200 becomes 1.50).
There’s no need to actually do these calculations, as you can just use a simple odds converter online. The table below shows five sample prices in all three odds formats:
| Decimal |
Fractional |
American |
| 1.50 |
1/2 |
-200 |
| 1.75 |
3/4 |
-133 |
| 2.00 |
1/1 (evens) |
+100 |
| 2.50 |
6/4 |
+150 |
| 5.00 |
4/1 |
+400 |
Note: American odds are rounded to whole numbers, so some conversions are approximate (1.75 is shown as -133, although the exact figure is -133.33).
Implied Probability and the Vig
Implied probability is the likelihood of an outcome as expressed by the odds. To calculate a bet’s implied probability, you simply divide 1 by the decimal odds and then multiply that figure by 100.
Let’s stick with the example used above:
- New York Knicks to beat Miami Heat (1.75)
- Miami Heat to beat New York Knicks (2.10)
Odds of 1.75 imply that the Knicks have a 57.14% chance of winning the game (1 ÷ 1.75 x 100 = 57.14). Meanwhile, odds of 2.10 give the Heat a 47.62% implied chance of securing victory (1 ÷ 2.10 x 100 = 47.62).
You’ll notice that the implied probabilities don’t add up to 100%. There’s an overround of 4.76% (57.14% + 47.62% = 104.76%). That is the sportsbook’s house edge. It’s also known as the juice or vigorish – shortened to vig – in the US.
The vig gives the sportsbook a strong chance of earning a margin. Think of it as a built-in commission for the service of taking bets. It helps the company cover its operating costs and generate profits.
You’ll significantly boost your chances of earning a long-term profit if you consistently place bets with low vig. Get into the habit of checking the overround before you bet: convert the odds to implied probabilities and add up the market. The closer to 100% it is, the fairer the price. Train yourself to notice when a book’s margin is unusually low, as those markets offer the best value.
Crypto Sportsbook Odds Explained
The odds at crypto sportsbooks are normally displayed in the decimal format. If you want to change to a different format, select the “Settings” or “Preferences” button. There should be an “Odds Display” or “Odds Format” option. You’ll then get a dropdown menu, so you can choose decimal odds, fractional odds, or American odds.
If you find a bet you like, click on the odds to add the pick to the betslip. You can then enter the amount you’d like to risk, and the slip will tell you how much you stand to win. If you’re happy, just click to confirm the bet.
Conclusion
When you know how to read betting odds, you can size up any market. You’ll quickly understand the implied probability of the bet winning, the potential profit on offer, the margin the sportsbook is taking, and whether the bet offers value.
FAQs
Odds of 2.50 mean you’ll get a return of $2.50 for every $1 you bet if the pick is correct. For example, a $10 bet at odds of 2.50 would return $25, while a $20 bet at 2.50 would return $50. That includes your profit and the return of your stake.
Odds of +200 mean you’ll earn a $200 profit for every $100 you risk if the bet wins. American odds of +200 are equivalent to fractional odds of 2/1 and decimal odds of 3.00. They imply a 33.3% chance of the bet winning.
To convert fractional odds to decimal odds, divide the numerator (the top number) by the denominator (the bottom number) and then add 1. For example, fractional odds of 4/1 convert to 5.00, while odds of 9/2 convert to 5.50. Fractional odds tell you the profit you’d earn from a winning bet, whereas decimal odds highlight your total return (profit plus the return of your stake).
Implied probability turns betting odds into a percentage, showing how likely the market thinks a specific outcome is. For example, odds of 1.50 imply a 66.7% chance of a bet winning, whereas odds of 12.00 imply an 8.3% chance of the bet succeeding. This is why you earn bigger profits by successfully betting on underdogs.
Ilija is a CCN writer with 7 years of experience covering all things crypto. Ever since a fateful run-in with Litecoin in 2013, he's been an avid investor and writer in the space. When he's not maniacally hacking away at his keyboard, Ilija spends his time either hiking in nature or holed up in his apartment gaming.
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