Initial Preflop raises

Ok we all know that in NLHE, a standard raise is 3-5 x BB + 1BB per limper.

Where did that range actually come from?

I dont mean who wrote it first, although that might be of historical interest.. but whats the logic behind that being the standard preflop range?

Why not 4-7 or 5 - 10?

Just been thinking and wondered if anyone could throw some light on it.

It's essentially based on the concepts of a) giving your opponent enticing enough odds to call while still charging them a significant price, and b) cheap enough for the raiser to have fold equity while not committing too much when he's got lesser holdings.

well starting at the very very basics, why do you raise? to give your opponent the opportunity to make a mistake. when you have a better hand, you want him to call, and when you have a worse hand, you want him to fold. now lets look at both extremes: raising huge and min-raising (ignore range of hands you raise with for simplicities sake). if you raise say x20BB, you can assume people will only call or raise you with a better hand (and not make a mistake for the most part), and usually correctly fold, although occasionally they may have a better hand. as you can see by raising big you are making it easy for your opponents to make the correct decision. if you min-raise, more often than not they are going to get the correct odds to call even if they don't have the best hand, therefore making the correct play. also, by players doing this, your opponents are giving each other better odds to call. this makes it easier to be drawn out by donks when you have good hands, and you won't get big paydays when you beat them.

so it seems as if 3-5 x BB + 1BB per limper is simply the perfect in between of the two extremes. it has most likely been tested and worked out for experienced players, and has now become common.

Looking at the pot odds - if I raise to 3x, everyone folds to BB, the BB has to call 2BB to get at 4.5BB - that's better than 2/1, so he's got a reason to call with a reasonably wide range - while the SB has to call 2.5BB and everyone else has to call 3BB to get 4.5BB - not great odds for the other players, who would need to tighten their ranges - but it's not a raise that's so prohibitive that it keeps all players out who are dogs to my hand. The upper end of 4x or 5x creates worse odds for BB to call, so he ought to be tightening his range further, and everyone else should be tightening up to the accordingly poor pot odds. Creating pot odds that guarantees that only AA or KK will call is generally not a great value situation, and creating pot odds that anyone would call with ATC (i.e., min-raise followed by a call) is not a great FE situation.

Do you guys mind sharing your thinking here on varying the size of the bet given the reasons provided here, and how they relate to context? If I'm looking to have the opponent make a mistake, and gain FE and value out of my hands, what do you see as the most effective bet sizing strategies? What conditions cause you to vary the bet size outside of the +1 for each limper? Do you not vary the bet size?

i believe keeping your bet sizes consistent makes you unpredictable as to what you are holding. over the long run, if you randomly make you raises + or - 1BB/maybe 2BB to have some variety like you said, you will get the same results as keeping your bet sizes consistent. but since it is quite difficult for us humans to be "random", consistency is the way to go.

It depends on your opponents. 4x +1 is good, but if they will make a mistake by calling 8 times, then why not let them? Each table should be a bit different, so you just need to figure out what your table is playing like. If you have AA and you know that everyone will call an all-in, then go for it.

this is quite interesting. i've thought about it and found it more difficult to read someone varying there open raise. For example, let's say you're trying to read the aggressive player two seats to your right. so we're BB and the villain is consistantly opening from the button. now if it was the same 3xbb, it would be easier to pick a spot for a resteal. but lets say he changed it up and bumps it to 4.5x instead and then a few rounds later min raise. kinda confuses you for a sec and we end up folding.

The problem with this is keeping it random. If said villain min raised AA and KK and went to 4.5x for pure bluffs we would catch on eventually. This entire aspect is pretty overated though since people are not observant/dont play enough together to really catch on.

Good point. Against regs who you have thousands of hands they can look that stuff up. But it's going to take a few hundred hands at least with an opponent for them to realize what you're doing it with. And if you even arbitrarily (not randomly) throw in a few mixes, that makes it even longer until the opponent will catch onto the tendencies.

Also minraise preflop opens on the button are sweet .

To add to what everyone else has said.

This is from No limit Hold'em Theory and Practice. In regard to always preflop raising the same amount all the time "This advice strikes us like cutting of your leg to cure your athlete's foot." Then later on the same page, "...you can raise for a variety of reasons, some of those reasons prefer differently sized raises." Pg 111.

Anyway the point is that just becuase you raise AA 5xbb doesn't mean you always will. Why forgoe value because someone MIGHT get a read on you. Also if you are properly mixing up your play their read will be completely wrong, you don't even need to randomize it unless you playing against regulars, and you aren't seeking out the regulars who are good enough to actually use this against you, are you?

FTR - I always used to size my preflop raises the same but that is becuase I am lazy and it is easy to remember. I didn't have to think about it I just knew if I was raising I was going to raise xbb+1 per limper, etc. etc. No more thought given to that. I would venture a guess a lot of people you play against do the same thing (bad players obviously), they heard that it was correct to do and never really questioned it.

ok I have an additional question. Does this change if we're extremely deep? Extremely shallow? If you're sitting with 500 BBs do you still raise 3-4x? If you're sitting with 20 do you?

wow, we have similar insights...VERY similar insights...

Thats something I was wondering too.

Nowhere in the standard formula is the relative chip stack size taken into account.

and i assume that means opening ATC with a minraise, right? btw, how do you react to that if you're in the blinds? Flat a lot because you're getting great odds? 3bet lighter ?

Great point.
I was gonna babble something here,but there are some great answers already.

Villain depenent. generally I 3-bet 2 -> 9 BBs just to prevent them getting insane implied odds, and if they're minraising wide range yeah I'll 3-bet a bit lighter and flat good SC-type hands. Generally just depends on what opponent does though postflop. If they go crazy when played back at I'll just wait for premiums to 3-bet. Some play fit or fold postflop so I'll just flat a super-wide range and take all the pots they don't take.

I've watched tons of WSOP and WPT video and even at the end game most of raises are still 3-5xbb. After the flop hits all heck breaks loose. But 3-5 seems to be ingrained in everyone's head.

You don't want to put too much as risk and don't want to scare away the customers.