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How To Read Odds

Odds are arguably the most critical factor in all sports betting. Without them, there would be no edge to gain or discernible strategy in sports wagering other than predicting who will win games and matches. For this reason, knowing how to read the odds is crucial when betting on sports. If you ever wanted the nature of betting odds explained from the ground up, you came to the right place, as we will get into everything you need to know.

Why Are Betting Odds Important?

Nothing could be more important in sports betting than the odds. The goal of sports betting is to find odds that you feel are in the bettor's favour.


For this reason, it is crucial that you understand the meaning of betting odds and seek out the best numbers when looking to make profitable sports wagers. Understanding how to read odds and their ratios can determine a profitable bettor from a losing one.

How Are Betting Odds Calculated?

For anyone betting, it can be interesting and helpful to know how betting odds are calculated. Betting odds are set by sportsbooks based on the probability of events occurring in sporting events.


Sportsbooks use advanced metrics to determine the relative likelihood of outcomes in sporting events occurring. Odds are set based on these calculations and then gradually moved according to a range of variables which change in line with each sport's nature.

How to Read Betting Odds

You will, of course, want to understand how to read betting odds in various formats. Depending on your region, you will most likely see the same odds format, but it is wise to at least understand the different ways odds can be represented.


This way, you'll be able to read all formats effectively and quickly, which is particularly helpful when live betting since time is of the essence with in-game scenarios.

How to Read Decimal Odds

Decimal odds are often used in Canada and throughout Europe. With decimal odds, one number tells you what you would collect, making it easy to understand how to read decimal odds.


Instead of using a plus or minus sign or a fraction, a single positive number tells you what you would be paid out for every $1 you wager. For example, you might see a team favoured by 1.85.


This means that a $1 wager will garner you a $1.85 payout. To manually calculate your exact winnings, you would multiply that number based on the amount you are betting (a $10 wager would mean an $18.50 payout, etc.)

How to Read Fractional Odds

Fractional odds are very common in the UK, so you will want to know how to read fractional betting odds if you plan to wager there. These odds are expressed as fractions, meaning if American odds are +200, the fractional equivalent is 2/1.


Fractional odds are the amount you would win divided by the amount you are betting. What you would win (the fraction's numerator) is listed first, while what you are betting (the denominator) is listed second. For 2/1 odds, as an example, the numerator is 2, and the denominator is 1.

How to Read American Odds

American odds are, of course, what you will mostly see in the US. These are also considered the "moneyline" in US betting parlance. An example would be a favourite set at -150 while an underdog is +135.


You must wager $150 on the favourite to win $100. In contrast, a $100 bet on the underdog will garner you a $135 win.


The above example helps us understand how to quickly scan and interpret American odds. A negative (-) number equals what you have to bet to win $100. On the other hand, a positive (+) number equals what you would win if you bet $100.

How to Convert Betting Odds

Here we will explain how to calculate odds from all standard formats into all others. Using a betting odds converter is the most convenient means, but it can be done manually in a pinch.

Calculating Decimal Odds to Fractional Odds

To calculate decimal odds to fractional odds, the formula is straightforward.

Take the decimal and subtract 1, so:


5 – 1 = 4/1


The simple conversion will not be as precise if the decimal is not .00 but will get you close, for instance:


4.50 – 1 = 3.5/1 or 7/2

Calculating Fractional Odds to Decimal Odds

Conversion of fractional odds to decimal format is also simple. Take the first figure and divide it by the second, then add 1. So:


1/2 becomes 1 / 2 + 1 = 1.50


For another example:


2/1 becomes 2 / 1 + 1 = 3.

Calculating Decimal Odds to American Odds

Decimal odds to American odds conversion involves two different formulas depending on whether decimal odds are above or below 2.00.


To convert decimal odds of 2.00 or greater, the following formula is used:


US odds = (Decimal – 1) x 100


Please see the below example using decimal odds of 2.50:


Decimal odds = 2.50


US odds = (2.50 – 1) x 100 = 1.50 x 100 = +150


The decimal-to-American odds formula is different if the decimal odds are less than 2.00:


US odds = (-100) / (Decimal – 1)


Please see this example using decimal odds of 1.50:


Decimal odds = 1.50


US odds = (-100) / (1.50 – 1) = (-100) / 0.50 = -200

Calculating Fractional Odds to American Odds

Fractional to positive American odds conversion involves taking the value of fractional odds and multiplying it by 100.


An example would be:


3/1 x 100 = 300, or +300 in American odds form.


To convert fractional to negative American odds, you divide -100 by the value of the fractional odds.

For example:


-100 / 1/5 = -500

Calculating American Odds to Decimal Odds

To convert positive American odds to decimal odds, the formula is:


(American odds / 100) + 1 = decimal odds


Let's use the example of American odds of +120:


(120 / 100) + 1 = 2.20 (decimal odds)


For negative American to decimal odds, the formula is a bit different:


1 – (100 / American odds) = decimal odds


Using the example of American odds of -140:


1 – (100 / -140) = 1.71 (decimal odds)

Calculating American Odds to Fractional Odds

Converting American odds to fractional involves different formulas depending on whether the American odds are positive or negative.


For positive American odds, the formula is:


American odds / 100 = fractional odds


Let's take a look at how this would work with odds of +120:


120 / 100 = 1.2 = 12/10 = 6/5


You will note that 12/10 had to be converted to the equivalent 6/5.


For negative American odds to fractional conversion, we are looking at this formula:


 -100 / American odds = fractional odds


To use odds of -140:


-100 / -140 = 0.71 = 7/10 = 3/5


Again, this formula requires a conversion of 7/10 to 3/5, which is not exact. This is where conversion to fractional odds can be less than perfect as one must round numbers at times to how they would be represented fractionally.

Why Do Betting Odds Keep Changing?

Betting odds are constantly moving as theScore Bet Sportsbook and Casino adjust them to account for the action coming in on different sides. There are also other reasons, such as injuries, weather, and other factors that affect the actual likelihood of outcomes occurring.

What to Look for in Betting Odds?

You are trying to find odds that give you a higher chance to win than they would indicate. Perhaps breaking news has resulted in an inefficient line that has yet to be moved in lieu of reports.


You may have a take based on your research that you don't believe odds are taking into account. You can also use an odds margin calculation as a means of trying to find value in odds.

Reasons to Bet with theScore Bet®

If you are looking for the best online betting app to test out your ability to beat the odds, theScore Bet® is the place to be. Not only is mobile compatibility a breeze, but we pride ourselves on our reputation for safety and reliability, as well as our sign-up offers.

How to Read Odds FAQs

How do betting odds work?

Betting odds represent the amount of money you have to bet to win a certain amount - if the outcome you bet on comes true. They are set by sportsbooks based on the likelihood of events occurring, considering profit margin based on either outcome.

How to read betting odds?

Depending on whether odds are decimal, fractional, or American, reading them is slightly different. Still, all formats represent what you have to wait or to win a given amount relative to the bet.

What to look for in betting odds?

You want to look for odds that give you relative value compared to the actual likelihood of an event occurring. You can use calculations to ascertain this and may also find odds that appear inefficient based on your knowledge of the sport.

What does betting against the odds mean?

Betting against the odds is to bet on the underdog, which will be the side that offers a higher payout for your wager based on the odds.

How to read the real value of bets?

The best way to ascertain the actual value of a bet is to use odds margin calculations to see what the house would be gaining, assuming both sides were to win 50% of the time.

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