ONLINE POKER 101: Step 4, The Rule of 4 and 2

Posted by Pajamas Poker on November 8th, 2009

Yesterday we touched on the basics of counting your outs, and today we are going to build on that by using your number of outs to quickly calculate the rule of 4 and 2. To start out let’s work with a basic two card hand along with a fresh flop.

Hold Cards:

The Flop:

As you can see, any heart and you can make a flush which is nine outs:
h10

Also, any four also makes you a straight (make sure not to count the four of hearts a second time), which is three outs:

Add up all of your outs for a total of twelve outs, remember to not count under-pairs as outs. You may pair your six or five of hearts but seeing as there is a seven and a queen on the board you need to assume that someone has paired either of those, so don’t consider those cards as outs. After you have tallied your outs it is time to use the rule of 4 and 2 to quickly calculate your chances of having a winning hand.

The Rule of 4
After the flop, multiply your number of outs by 4 to determine your chances of making your hand on the river. For example, multiply the 12 outs above by 4; 4 × 12 = 48% So you have a 48% chance of making your hand by the river.

The Turn

After the turn the number of outs has increased, the eight gives you three more outs with the remaining nines in a straight draw so there are now 15 outs.

The Rule of 2
The rule of 2 works just like the rule of 4. After the turn, you multiply your number of outs by 2 to determine your chance of making your hand by the river. For example, multiply the 15 outs above by 2; 2 × 15 = 30% So you have a 30% chance of making your hand on the river.

Simplified
With the rule of 4 and 2 you multiply your number of outs by 4 after the flop or by 2 after the turn to calculate your chances of making your hand on the river.

Using the rule of 4 and 2 you can quickly and easily calculate your odds of catching your winning hand by the river. Now in the above example 30% on the turn isn’t a great chance but 15 outs is still substantial and depending on the bet and the table you may want to ride out that hand until the river. In our next post we’ll delve even deeper into what you should do in this situation by telling you how to calculate pot odds, so check back tomorrow for that.