Outs are the number of cards there are for you to make a particular hand that you figure to be the best hand.

For example, You have the 10J of spades and the flop comes 4-hearts 5-spades 6-spades.

You need a spade to make your flush which figures to be the best hand most of the time.

There are 52 cards and 13 of each suit. We have 2 spades and there are 2 spades on the flop so that leaves 9 (13-2-2) remaining spades in the deck.

Therefore we have 9 outs.

Now, lets assume we have 10J spades and the flop comes 2-diamonds Q-clubs K-hearts.

Here we figure we need to make a straight to have the best hand.

We would need a 9 or an Ace to complete our straight draw.

Knowing that there are four of each card we need one of 4 nine's or one of the 4 Aces.

This means we have 8 outs to complete our straight draw.

Inside Straight draw (or gutshot) = 4 outs

Two over cards = 6 outs

Inside straight draw with two over cards = 10 outs

Open ended straight flush draw = 15 outs

Flush draw with two overs (AK suited) = 15 outs

First we will learn post flop pot odds.

For this we will use the rule of 4 and 2 which will give us nearly the exact pot odds.

We have our favorite hand 10j spades and the flop comes 4-hearts 5-spades 6-spades.

Now we know we have 9 outs to complete our flush draw.

But what percentage of the time will we make our flush?

For calculating pot odds on the flop we use 4 and times that by the number of outs.

So our chance of hitting a flopped flush draw (2 cards still to come) is 4 x 9 = 36%.

So now we know we make our flush slightly better then 1 in every 3 tries (33.3%).

If we flop an open-ended straight draw we have 8 outs x 4 = 32% (less than 1 in 3 tries).

Two over cards is 6 outs x 4 = 24% (little less than 1 in 4 tries).

What if we want to know what our pot odds will be after the turn card is dealt?

This is where we use 2.

For a flush draw after the turn we still have 9 outs x 2 = 18% (less than 1 in 5 tries; or 4:1)

For an open ended straight draw - 8 outs x 2 = 16% (just less than 1 in 6 tries; or 5:1)

For a gutshot straight draw - 4 outs x 2 = 8% (just 1 in 12.5 tries; or 11.5:1)

Here are the Main pre-flop pot odds that you should know (approx. %).

Overpair vs. Underpair (e.g AA vs. 88)

-80% to 20%

Underpair vs Two Overcards (e.g. 99 vs. AK)

-55% to 45%

Pair vs. One Overcard (e.g. QQ vs AJ)

-70% to 30%

Now you know how to calculate pot odds.

Now that you know how to calculate your pot odds it is the size of the pot that determines if you should call or fold. Let's look at an example.

You have a flush draw with one card to come. You figure you are behind in the hand but that a made flush would win the hand for you.

We now know that we will complete our flush 1 in 5 times (or 4:1; 4 times we don't make a flush - 1 time we do make a flush).

Assume our opponent goes all-in for his last $20 into a $40 pot. This makes the total pot size $60.

We are facing a call of $20 to win $60. The pot is 3 times the size of the bet meaning we would need to be getting 3:1 pot odds to break even in the long run.

Since we know our flush draw is 4:1 we should fold. Now let's assume your opponets is betting $20 into an $80 pot for a total pot of $100.

Here we are getting 5:1 on our money ($100/$20).

Since our flush draw is 4:1 we should make the call. Over the long run we will lose 4 times for a loss of $80 and win it 1 time for a gain of $100 resulting in an overall profit of $20.

In the example above we are simplifying things by assuming our opponent is going all in for his last $20.

But more often than not this will not be the case.

What if our opponent bets $20 but his still has $80 in his stack.

This is when we have to consider implied odds.

For more information check out our article on __implied odds__.