Introduction to calculating odds and percentages

Every poker player who has ever sought to increase their knowledge of the game has probably heard of poker odds and percentages. In this article, we'll give you a very basic and accessible introduction to this subject.

Calculating poker odds

When we read someone saying "I had odds of 4:1" what does that mean? Let's look at two examples to learn how to better interpret this data.

Example 1: If someone gives us odds of 4:1 or 4 to 1, we can interpret this to mean that we need to win 1 out of every 5 times in order to breakeven in the situation used (0 to 0). We could also say that every 4 times we lose we have to win 1, making a total of 5.

Example 2: If the pot has $14 on the river and we need to pay $4 to win it, what are the odds for the call? Since the size of the pot is $14 and we need to pay $4, let's describe it as 14:4 or 14 to 4. We want the second side to be reduced to 1, so we divide the first number and the second number by the second number: (14/4):(4/4) = 3.5:1.

Converting odds into percentages

Example: To calculate the percentage we have of winning using the odds of 4:1, we first add up 4+1 and put this number as the denominator. In the numerator we put the number 1. So 4:1 odds are actually 1/5 or 0.20, which is the same as 20%.

Some common odds converted into 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%

Converting poker percentages to odds

First we divide the percentage by 100 to get a decimal number. We then subtract this number from 1. Step 3: the resulting decimal goes on the right and the previous one on the left. Step 4: we then reduce both sides to arrive at the number 1 on the right.

Bonus, cashback & freerolls - you'll find all this and more when you create your PartyPoker account from our links!

Example 1: converting odds from 20%

Step 1: 20/100 = 0.20
Step 2: 1 - 0.20 = 0.80
Step 3: 0.80 : 0.20
Step 4: .80/.20 : .20/.20 = 4:1

Now that you know how to calculate the odds, all you have to do is practice reasoning using your previously acquired knowledge of outs, and relate the data, trying to always think about whether a move is profitable or not!

Example:

Player 1: :4s :5s
Player 2: :Jd :Jc

Board: :Qs :6s :8c :Kd

Our opponent has a pair, and in this case, the only cards that save us on the river are spades or a 7, for the straight.

Did you know that when you create your 888Poker account from our links you get a great bonus and you can also play our exclusive weekly freerolls?

Knowing this, we know that we have 9 outs from the flush and 3 from the straight, for a total of 12 outs - which represents a 27.2% chance of hitting a winning card on the river.

NOTE: In this example, we'll assume that we know our opponent's cards.

The pot is $1,000 dollars, and the villain bets $500. Should we call?

The odds are 2:1, or 33.3%.

Although the temptation is great, we will hit our hand fewer times than the number of times necessary to make this move profitable in the long term, according to the odds, so the right thing to do is fold.

Article translated and adapted from: Calculating Odds