Check-Raising As A Bluff

By Jack Wilcox

1 Apr, 2011

When your opponent raises pre-flop and gets a caller, they will frequently continuation bet the flop if it is checked to them. Very often your opponent is going to have nothing, because unpaired hole cards miss the flop 2/3rds of the time.

Therefore, they will generally have to fold to a check-raise.

You can start to check-raise a lot of hands, especially from the blinds when you call their late position raise, because this is when their range will be the widest and contain the most amount of air.

What are the benefits of check-raising as a bluff?

Check-raising as a bluff is great because of the fact your opponent has to fold so often. But also because if you just check-raise for value with sets/two-pair or huge draws, you become very easy to read, especially when your opponent checks your HUD stats and sees your check-raise% in the region of 5-9%.

Although I wouldn't say balance is the most important factor, you need to recognize that if you are showing up as a total nit to your opponents, they aren't going to give you action.

Check-raising as a bluff on occasion is fine if it's only costing you 10-12bb to make the bluff, but then earning you 100bb every time they call the flop and continue to call you down.

Who are you looking to check-raise as a bluff?

The ideal player would be someone who has a high steal%, high cbet% and low W$WSF, or a low check-raise%.

Generally, players tend to think that their opponents play in a similar way to themselves, and therefore someone with a low check-raise is likely to give you more credit, because they know they would rarely check-raise as a bluff themselves.

Of course, it's unlikely that you will find many opponents who fit all of these categories, so the main stats to look out for are high cbet% and a low check-raise%. The reason being that if you read on to the upcoming mathematics, you will see they don't have to be stealing much at all to be exploitable to a check-raise.

Why check-raise as a bluff?

A lot of people suggest floating the flop to see how your opponent reacts on the turn, and then stealing it from them on the river. There's a few problems with this:

1. Your opponent may pick up equity on the turn and decide to barrel as a semi-bluff, which makes you fold the best hand.
2. Your opponent may pot control marginal showdown value on the turn, with the intention to call a river bet (especially if any draws miss).
3. You cap your range by check-calling. On certain boards you would always check-raise with your sets or big draws (e.g. T78 two-tone) so by check-calling you represent weak hands, which cannot stand any real pressure on a lot of turns.

The mathematics behind a check-raise bluff.

The button raises to 3bb. The small blind folds, and we call in the big blind. The pot is 6bb.

The flop comes

We check, and our opponent bets 4bb. We check-raise to 11bb.

We assume that they will always call a bet with 88-AA, 44 and Qx (assume Q7s+ and Q9o+), and we assume they will fold anything else.

When called, we assume we have no equity and will give up. Therefore the fold equity we require on a bluff is:

11/(10+11) = 0.52 (or 52%)

This is because we risk 11bb (which we lose if they call, and is expressed as the first half of the sum), and we win 21bb when they fold (the 10bb in the pot after their continuation bet + our 11bb check-raise).

The hands that they continue with amount to: (using PokerStove for this analysis)

• 6 combos of each pocket pair, and we think they continue with 7 pairs (excluding QQ), so 42 combos.
• 2 combos of each Qx suited hand, which amounts to 7 Qx suited for 14 combos.
• 6 combos of each Qx offsuit hand, which amounts to 5 Qx offsuit for 30 combos.
• 1 combo of QQ and 3 combos of 44.

They continue with a total of 130 combos of hands, which sounds like a lot. However, there are only 1,326 combos of starting hands in Texas Hold'em, so it's only 10% of starting hands that can continue after you check-raise the flop.

If we assume they are opening 40% from the button, and continuation betting 75% on this flop, they will have:

1326 * 0.4 * 0.75 = 397 combos

Therefore they will be continuing only 130/397 = 32%, and therefore folding 78% (allowing us to print money).

If you increase or decrease the amount they are opening or continuation betting, then you can easily see how it affects the amount of hands that can continue to a check-raise here. You can also change the board texture and change the amount of hands you think continue against a check-raise, before re-calculating their range to see how that affects you.

What boards are good to check-raise as a bluff?

Paired boards like the one above are good, particularly paired boards which are rainbow and have no straight draws, along with one high card. This is because in the above situation you can actually have a decent value range; AQ, KQ, QJ, and QT are all well within your range, and fit with how you would probably want to play them.

Of course, not many flops will come QQ4r, so other flops you should look to check-raise on are rainbow flops with one high card, such as J63. You want one high card because a lot of people will automatically cbet those type of boards, but may check back a lot more on 863, thinking that they don't represent much by betting.

Furthermore, you ideally don't want there to be a flush draw, as it increases the chance that:

1. Your opponent has a draw themselves and can call.
2. Your opponent puts you on a draw, and is more likely to hero-call you down.

Basically, when check-raising as a bluff, you want to be doing it on boards where if you have the value hand that you are representing and your opponent doesn't, then your opponent has almost no equity. So on QQ4, if you have a Q and your opponent doesn't, its really hard for them to improve. Similarly on J63r, if you have a set or Jx and your opponent doesn't, it's hard for them to improve.

Therefore, it becomes a lot more about "do I think they are bluffing or not?" as opposed to "they can have a lot of draws, and I have enough equity to call and see whether they miss...".

Does it matter what you have?

Not really.

If you check-raise a super dry board and your opponent calls, it's generally going to be because they have a huge hand.

A lot of people would tell you to check-raise with outs, such as with 2 overcards where you can hit one of them on the turn. However, consider a board like:

If you check-raise and your opponent calls, a decent part of their range will be Tx, 55, or overpairs. So check-raising a hand like QJ and hitting the J on the turn is not actually good for you, because now it will be difficult to get away from the hand, even though you aren't doing very well against your opponent's range.

We saw in the mathematics section that check-raising any two cards is profitable against most people, so for the most part it will just come down to if they give you credit for having it.

But overall, you should be more focused on picking spots based on gameflow. For example, think “I have been quiet for a while, they should give me some respect here”, rather than “I have hand X, I should go ahead and check-raise”.

Jack.