Hold'em Outs Counting - 2-4 Rule

[Brad22]

Is this rule sufficient enough for most situations in hold'em?

Are there any tables or ways to figure out how to discount outs based on:
-what your opponents may be holding
-cards that can hit that would help you and oppenent

Your outs are always dependant on what your opp. is holding (what you must hit to beat him)

If cards that hit help you, but also help him more (as in they make two pair for you but give him his flush) you need to remove those outs:

Ac Jc
vs
Qd 4h

flop is Qc 2c Ah

Now then... you can hit 2 queens, and 2 fours (minus the four of clubs) for a total of 4 outs... 16%, 5 to 1. Badda bing badda boom. Don't worry about the slight percentage difference that his flush draw creates... If another card hits on the turn that improves your hand, you just recalculate from there as to his outs.

That extra chance of him hitting then becomes the amount that you would depreciate your initial chance of winning. your initial chance is 16% here
If you hit on 4th street, he then has 9 clubs, 2 Aces , 2 J for 13 outs = 26% for him to strike back on 5th.

26% of 16% is about 4%. 16% - 4% is 12%. So your overall percentage from the flop is closer to 12 than to 16, but will marginally appreciate somewhere closer to 12.5 for other complex reasons...

There are a lot of little complicated fractional adjusters for percentages that shift them away from the "base percentages" for the situation. I am actually writing a guide for these, so one can easily remember all of them in one "currency" (expressed as fractional numbers of outs) and easily adjust for things such as a runner runner board overpair, or the chance of a runner runner str...

Note that you should NOT be banking on these partial outs, or even using them in your games (only use pure outs to calc live) but it is nice to know sometimes to improve your calculating skills and impress your friends when you can call the EXACT percentages before the WPT broadcast puts them up...

One important thing about the 2-4 rule is that it does not work for outs above 15 or so.. nor can you use the same logic to calculate outs above 5 preflop. Just know that as you head beyond 16 outs the law of diminishing returns on marignial investment kicks in and you don't improve much beyond 55% to win...

Keep an eye out for my upcoming indepth odds post if you want to know the riveting details of how sharing suits or controling straight cards in preflop confrontations marginally affect the winning percentages... sounds fun, no?

[Brad22]

Yeah, tons of fun, hehe.

Basically, 2-4 seems more than sufficient to make the correct calls and folds in Hold'Em. I'm sure the #'s are a tiny bit jaded here and there, but close enough.

[Copernicus]

It is definitely close enough. Calling odds are not a green light/red light situation and the EV error from even knowingly taking the worst of it by a few percent isnt going to change your results materially.

Hell, Josh Arieh didnt learn until last week that if you are 25% to win you only need 3:1, not 4:1 to break even.