How To Convert Odds

How do you convert odds into their implied probabilities? And how do you convert implied probability into the range of popular odds formats? Use our odds conversion calculator or learn the formulas behind.
Knowing how to convert betting odds can be very helpful. In fact, if you don't know how to convert betting odds into their respective implied probabilities, you're not helping your chances of coming away as a long term winner in the competitive world of sports betting. Understanding the implied probability behind the odds on offer is key to assessing the potential value in a particular betting market. And it is just as important when assessing the value that exists with regards to specific odds on a particular outcome. If the implied probability is less than your own assessed probability of a particular outcome occurring, that outcome represents a value betting opportunity.
Converting Odds To Implied Probability
Typically, there are three kinds of odds you will come across in the sports betting landscape.
 Decimal odds: represented as 1.65 or 2.95 etc.
 Fractional odds: represented as 5/2 or 3 to 2 'on' etc.
 Moneyline odds: represented as 120 or +140 etc.
They all reflect the same thing, the return you will receive on a given amount of money placed on a bet. To convert your odds to implied probabilities or an implied probability to odds, you can either use our odds conversion calculator or do it by hand with the formulas provided below the calculator.
Odds Conversion Calculator
Converting Decimal Odds
Decimal odds are a simple reflection of the return you will receive for each single unit placed. For example, let's say bookmaker Matchbook is offering odds of 1.65 for Manchester United to win. This means that for every 1.00 you bet on that particular outcome, you will receive a profit of 0.65 should Manchester United win.
To convert these odds to their respective implied probabilities we make a simple calculation.
Converting decimal odds to implied probability formula:
Implied probability  =  1 / decimal odds 
Let's look at an example, in which Diego Costa to get a yellow card is odds 1.65.
Example: How to convert decimal odds to its implied probability
1 / 1.65  =  0.606  =  60.6% 
Multiplied then by 100 to express as an implied probability percentage of 60.6%.
Converting Fractional odds
Fractional odds are generally the most traditional form of expressing betting odds. They are a simple reflection of the return you will receive for a particular amount bet.
So for example, let's say bookmaker Ladbrokes is offering odds of 5/2 for a particular horse to win an upcoming race. The odds of 5/2 (expressed as "5 to 2") means that for every 2 units that you bet, you will receive 5 back as profit. So if you bet €200 on that horse, you would have received €500 profit in return plus your original stake of €200.
Converting fractional odds into implied probability formula:
Implied probability  =  denominator / (denominator + numerator) 
Let's look at an example, in which Diego Costa to get a yellow card is odds 5/2.
Example: How to convert fractional odds to its implied probability
5 / 2  =  2 / (2 + 5)  =  2 / 7  =  0.2857  =  28.57% 
Multiplied then by 100 to express as a implied probability percentage of 28.57%
Converting Moneyline Odds
Moneyline odds, also known as 'American odds' are probably the most foreign odds format to those of us outside of North America. And at first they appear a little confusing. But it is helpful to understand what these odds represent especially when listening to Americans speaking about gambling odds in sports broadcasts or podcasts. So, let's see how we can convert Moneyline odds into their respective implied probabilities.
There are two instances of Moneyline odds: 'minus' moneylines and 'plus' moneylines.
The first are 'minus' moneylines. This is expressed as for example, 120. But what does this mean exactly? Well, let's say bookmaker bet365 are offering odds of 120 for the Los Angeles Lakers to win a game. This is essentially saying that to win $100 you have to bet $120. In other words, if you place $120 on that outcome, you will receive a profit of $100.
The other instance are 'plus' moneylines. This is expressed as for example +180. In this case, let's say bookmaker Winner Sports have offered odds of +180 for the New York Yankees to win a game. This simply means that if you bet $100, you will win $180.
So how do we convert the the 'minus' and the 'plus' moneyline odds into their implied probabilities? Let's start out with the 'minus' moneyline conversion:
Converting 'minus' moneyline odds into implied probability formula:
Implied probability  =  (  ( 'minus' moneyline odds ) ) / (  ( 'minus' moneyline odds ) ) + 100 
So let's take an example, in which Titanbet offers the following bet: San Diego Chargers to win against New England Patriots at odds 120.
Example: How to convert 'minus' moneyline odds to its implied probability
( (120) / ( ( (120) ) + 100)  =  120 / 220  =  0.545  =  54.5% 
Multiplied then by 100, we get the implied probability percentage of 54.5%.
Converting a 'plus' moneyline is a bit different. Calculating the implied probabilities on these look like this:
Converting 'plus' moneyline odds into implied probability formula:
Implied probability  =  100 / ( 'plus' moneyline odds + 100 ) 
So let's take an example, in which Paddy Power offers odds +180 for Los Angeles Lakers to beat Miami Heat.
Example: How to convert 'plus' moneyline odds to its implied probability
( 100 / 180 + 100 )  =  100 / 280  =  0.357  =  35.7% 
Multiplied then by 100, we get the implied probability percentage of 35.7%.
How Do We Convert Implied Probability Into Odds?
Knowing how to convert one form of odds to another can be helpful, especially if you have come into possession of a large amount of betting data that has odds formatted in an unfamiliar way.
To do this, we first need to convert any odds format to their implied probability. Once we have done this, the calculations are fairly straight forward.
Converting Implied Probability Into Decimal Odds
Converting implied probability into decimal odds formula:
Decimal odds  =  100 / implied probability 
Let's take an example. In this example we think that Arsenal has a 75 % probability of defeating Stoke. To calcluate our decimal odds target, we want to covert 75 % into odds:
Example: How to calculate implied probability to decimal odds:
100 / 75  =  1.33 
Implied probability of 75% would return decimal odds of 1.33.
Converting Implied Probability Into Fractional Odds
Convert implied probability into fractional odds formula:
Fractional odds  =  ( 100 / implied probability ) 1 
Let's look at an example, where we think Wayne Rooney has 25% probability of scoring a goal. In this example, the fractional odds target will be calculated as:
Example: How to convert implied probability to fractional odds:
(100 / 25)  1  =  4  1  =  3 
The outcome of this formula is 3, meaning we will express the odds as fractional odds = 3 to 1.
Converting Implied Probability Into Moneyline Odds
Converting implied probability into moneyline is a bit more complicated than converting it into decimal or fractional odds. The calculation depends on whether the implied probability is above 50% or below.
When the implied probability is above 50%, we make the following calculation.
Convert implied probability (50% and above) into moneyline odds formula:
Moneyline Odds  =   ( implied probability / (100  implied probability)) x 100 
Let's look at an example, where we think Lionel Messi has a 75 % chance of scoring against Levante. In this example, the moneyline odds target will be calculated as:
Example: How to convert implied probability (50% and higher) to moneyline odds:
 (75 / (100 – 75)) x100  =   (75 / 25) x 100  =   3 x 100  =   300 
Moneyline odds =  300.
When the implied probability is below 50%, the calculation is adjusted a little.
Convert implied probability (below 50%) into moneyline odds formula:
Moneyline odds  =  (100  implied probability / implied probability ) x 100 
Let's look at an example, where we think Niclas Bendtner has a 25 % chance of scoring against VfB Stuttgart. In this example, the moneyline odds target will be calculated as:
Example: How to convert implied probability (below 50%) to moneyline odds:
((100  probability)/(probability) x 100)  =  ((75) / (25) x 100)  =  3 x 100  =  300 
Moneyline odds = + 300.
Odds Conversion Chart
As a quick comparison guide, we've created an odds conversion chart which displays the odds and implied probability across each odds format.
Implied Probability %  Decimal Odds  Fractional Odds  American Odds 

99.0  1.01  1/100  10000 
98.0  1.02  1/50  5000 
97.1  1.03  1/33  3333 
96.2  1.04  1/25  2500 
95.2  1.05  1/20  2000 
94.3  1.06  3/50  1667 
93.5  1.07  7/100  1429 
92.6  1.08  2/25  1250 
91.7  1.09  9/100  1111 
90.9  1.10  1/10  1000 
90.1  1.11  11/100  909 
89.3  1.12  3/25  833 
88.5  1.13  13/100  769 
87.7  1.14  7/50  714 
87.0  1.15  3/20  667 
86.2  1.16  4/25  625 
85.5  1.17  17/100  588 
84.7  1.18  9/50  556 
84.0  1.19  19/100  526 
83.3  1.20  1/5  500 
82.6  1.21  21/100  476 
82.0  1.22  11/50  455 
81.3  1.23  23/100  435 
80.6  1.24  6/25  417 
80.0  1.25  1/4  400 
79.4  1.26  13/50  385 
78.7  1.27  27/100  370 
78.1  1.28  7/25  357 
77.5  1.29  29/100  345 
76.9  1.30  3/10  333 
76.3  1.31  31/100  323 
75.8  1.32  8/25  313 
75.2  1.33  33/100  303 
74.6  1.34  17/50  294 
74.1  1.35  7/20  286 
73.5  1.36  9/25  278 
73.0  1.37  37/100  270 
72.5  1.38  19/50  263 
71.9  1.39  39/100  256 
71.4  1.40  2/5  250 
70.9  1.41  41/100  244 
70.4  1.42  21/50  238 
69.9  1.43  43/100  233 
69.4  1.44  11/25  227 
69.0  1.45  9/20  222 
68.5  1.46  23/50  217 
68.0  1.47  47/100  213 
67.6  1.48  12/25  208 
67.1  1.49  49/100  204 
66.7  1.50  1/2  200 
65.8  1.52  13/25  192 
64.9  1.54  27/50  185 
64.1  1.56  14/25  179 
63.3  1.58  29/50  172 
62.5  1.60  3/5  167 
61.7  1.62  31/50  161 
61.0  1.64  16/25  156 
60.2  1.66  33/50  152 
59.5  1.68  17/25  147 
58.8  1.70  7/10  143 
58.1  1.72  18/25  139 
57.5  1.74  37/50  135 
56.8  1.76  19/25  132 
56.2  1.78  39/50  128 
55.6  1.80  4/5  125 
54.9  1.82  41/50  122 
54.3  1.84  21/25  119 
53.8  1.86  43/50  116 
53.2  1.88  22/25  114 
52.6  1.90  9/10  111 
52.1  1.92  23/25  109 
51.5  1.94  47/50  106 
51.0  1.96  24/25  104 
50.5  1.98  49/50  102 
50.0  2.00  1/1  100 
49.5  2.02  51/50  102 
49.0  2.04  26/25  104 
48.5  2.06  53/50  106 
48.1  2.08  27/25  108 
47.6  2.10  11/10  110 
46.5  2.15  23/20  115 
45.5  2.20  6/5  120 
44.4  2.25  5/4  125 
43.5  2.30  13/10  130 
42.6  2.35  27/20  135 
41.7  2.40  14/10  140 
40.8  2.45  29/20  145 
40.0  2.50  3/2  150 
38.5  2.60  8/5  160 
37.0  2.70  17/10  170 
35.7  2.80  9/5  180 
34.5  2.90  19/10  190 
33.3  3.00  2/1  200 
31.3  3.20  11/5  220 
29.4  3.40  12/5  240 
27.8  3.60  13/5  260 
26.3  3.80  14/5  280 
25.0  4.00  3/1  300 
23.8  4.20  16/5  320 
22.7  4.40  17/5  340 
21.7  4.60  18/5  360 
20.8  4.80  19/5  380 
20.0  5.00  4/1  400 
19.2  5.20  21/5  420 
18.5  5.40  22/5  440 
17.9  5.60  23/5  460 
17.2  5.80  24/5  480 
16.7  6.00  5/1  500 
16.1  6.20  26/5  520 
15.6  6.40  27/5  540 
15.2  6.60  28/5  560 
14.7  6.80  29/5  580 
14.3  7.00  6/1  600 
13.3  7.50  13/2  650 
12.5  8.00  7/1  700 
11.1  9.00  8/1  800 
10.0  10.00  9/1  900 
9.1  11.00  10/1  1000 
8.3  12.00  11/1  1100 
7.7  13.00  12/1  1200 
7.1  14.00  13/1  1300 
6.7  15.00  14/1  1400 
5.0  20.00  19/1  1900 
3.3  30.00  29/1  2900 
2.5  40.00  39/1  3900 
2.0  50.00  49/1  4900 
1.0  100.00  99/1  9900 
0.7  150.00  149/1  14900 
0.5  200.00  199/1  19900 
Bookmaker Odds Settings
Most online bookmakers now offer alternative display options for their odds. Below you can see the odds options available at bet365. Simply check your preferred odds format and all odds in all markets offered by bet365 will appear in that format.
So let's sum it up.........
How To Convert Odds
Converting fractional odds to decimal we add the numerator to the denominator and divide the total by the denominator e.g 9/2 becomes 11/2 which equals decimal odds of 5.50. Then to convert decimal odds to their probabilities divide 1 by the decimal odds. e.g odds of 4.00, 1 divided by 4.00 equals a probability of 25%.
While there are many tools on the web that will help you convert odds to their implied probabilities and convert odds to other formats, it is still a good practise to understand the calculations behind these conversions. This will only help you better understand what the odds represent in terms of value as well as exercising your betting brain to think instinctively in terms of implied probabilities when odds are presented to you.
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