Optimal Bet Sizing
20 Jan, 2012
This is a guest post by Johnathan "thatssosick" Chan. He was a coach at Jack Wilcox's old HigherLevelPoker.com training site. I decided to transfer Jack's articles to this website in August 2020, and thought I'd include the articles by other coaches whilst I was at it.
Bet sizing is one of the most underrated aspects of poker. It is essential to size your bets appropriately base on what you are trying to achieve.
When I coach my students, we commonly come across spots where they have not put much thought in to their bet sizing. Many players just default to betting a certain percentage of the pot without analyzing it properly.
In this article I will run through two example hands, and explain how they could have won significantly more money by making seemingly minor adjustments to their bet sizing.
Example 1: Bet sizing against an inelastic range.
The following example was taken from a student that I coached.
Preflop: Dealt to Hero
Hero raises to $4, 4 folds, BB calls $3
BB checks, Hero bets $6.5
It does not make sense to cbet a sizing of
6.5bb in this spot, as it their continuing range on the flop is inelastic.
An inelastic range is a range that is insensitive to the bet sizing you make.
On this flop, this type of player is continuing a range of (
KK), and is folding everything else. With that range, they are not sensitive to your bet size. So if you bet
5bb, they will still continue either way. You can say its unlikely they continue with
KK if you bet something ridiculous like
50bb, but it does not make much sense to cbet that amount, so we can disregard that.
So in a spot where they are continuing an inelastic range (and we don’t have a legitimate hand), we should be betting on the smaller side. A bet of
4.5bb, or even
4bb works fine here against this type of player.
We will be saving at least
1.5bb when we get called. Relative to a winrate of
1.5bb is significant.
Example 2: Building the biggest pot possible.
That was a simple spot. Lets look at a slightly more complicated one.
My student is still playing 100NL. Villain is an unknown, but seems to be a straightforward
20/18 with a
6% 3bet. We have only played 100 hands together, so we don’t have any history.
Hero (CO): $100
Preflop: Dealt to Hero
2 folds, Hero raises to $3, 2 folds, BB calls $2
BB checks, Hero bets $4, BB calls $4
BB checks, Hero bets $10, BB calls $10
BB checks, Hero bets $26, BB calls $26
Hero shows three sevens.
BB mucks two pair, Kings and Queens.
Hero wins pot $87.
Good result for my student — she wins an
87bb pot. But once we flop a set, our first thought should be thinking about how to get as much money into the pot as possible.
Against a villain who has not seen us play much, cbetting
4bb is a leak, because it's a flop where their continuing range is inelastic once again. They will be continuing a range of
Kx, flush draws,
7x, and maybe
66. Besides the
66 range, they will be calling with the rest of their range to any bet between
7bb (the size of the pot).
Betting full pot would make us look extremely strong, so I would advise to bet
5.5bb instead. You might be thinking it's only
1.5bb more, but you have to remember pot sizes grow exponentially.
Turn pot size would now be
This means we can bet
15bb on the turn, rather than
10bb. Their range for continuing on the turn is
Kx and some flush draws, and once again it is inelastic. They will be folding hands like
88 whether you bet
River pot size would now be
Q comes on the river. Their range is
KQ, and missed draws. The missed draws are not calling no matter what. It's also very likely
KQ is calling no matter what, and
Kx calls some percentage of the time. Looking at this range, you should be looking to bet big, as most of their range is calling a bigger bet more often than not.
A bet size of
40bb is appropriate. The flush draw missed, and it's plausible that villain will look at the missed draws and big bet size and try bluffcatching with
Villain calls with two-pair and the pot is
41bb extra to the original
87bb pot my student won. With a
5bb/100 winrate, that's 800 less hands you need to play.
Bet sizing is not as simple as betting big when you have a good hand and smaller when you don’t.
With these examples I wanted to illustrate the importance of thinking about your bet sizing, how much it can affect your play, and at the end of the day, your winrate.