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Below is a brief introduction to calculating odds and percentages in poker. Let this article entice you to learn more about odds and percentages and how important they are to become a successful poker player.

Calculating Odds

When we read that someone “was getting 4:1 odds” what does that mean? Let us look at two examples to learn how to interpret odds as presented to us.

Example 1: If someone gives us 4:1 or 4 to 1 odds, we can interpret this as needing to win 1 out of 5 to be breakeven. We can also explain this as for every 4 times we lose we have to win only once, thus 5 instances total.

Example 2: The pot is $14 on the river and we have to call $4 to win it; what are our odds to call? Since the size of the pot is $14 and its $4 to call, we describe that as: 14:4 or 14 to 4. We want the right hand side to be reduced to 1 so we divide both the left number (14) and right number (4) by the right number (4). (14/4):(4/4) = 3.5:1

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Converting Odds to Percentage

Example: To calculate the percent chance we need to win given 4:1 odds, we first must add 4+1 and put that number in the denominator. In the numerator we just put the number 1. So 4:1 odds becomes 1/5 or .20; then multiply by 100 to get the precentage: 20%.

Common Other Odds Converted to Percentages:

        5:1 = 16.7%

        3.5:1 = 22.2%

        3:1 = 25.0%

        2.5:1 = 28.6%

        2:1 = 33.3%

        1.5:1 = 40%

        1:1 = 50%

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Converting Percentage to Odds

Step 1: First we must divide the percentage by 100 to get a decimal. Step 2: We then subtract that number from 1. Step 3: The resulting decimal goes on the right side and the previous decimal on the left. Step 4: We then reduce both sides until we get to the number 1 on the right.

Example 1: Convert 20% to Odds

        Step 1: 20/100 = .20

        Step 2: 1 - .20 = .80

        Step 3: .80 : .20

        Step 4: .80/.20 : .20/.20 = 4:1

Example 2: Convert 22.2% to Odds

        Step 1: 22.2/100 = .222

        Step 2: 1 - .222 = .778

        Step 3: .778 : .222

        Step 4: .778/.222 : .222/.222 = 3.5:1

Example 3: Convert 33.3% to Odds

        Step 1: 33.3/100 = .333

        Step 2: 1-.333 = .667

        Step 3: .667 : .333

        Step 4: .667/.333 : .333/.333 = 2:1

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Hopefully this article has introduced you to the calculation of odds and percentages and how to use them in a poker pretext.