The Powerful Rule of 2, 4, and 5

A few years back, in an article in Blackjack Confidential magazine, I first detailed an idea that has proven to be among the most useful tournament strategy shortcuts that I know. The “Rule of 2, 4, and 5” allows you to quickly determine an optimal bet in many situations where you are trailing the table leader, but must bet ahead of him. This tool belongs in every tournament player’s bag of tricks, and deserves another look. While I’m at it, I’ll add a few extra items to the mix.

One of the more frustrating spots at a tournament table is when you’re behind in chip count, and betting in front of the leader. No matter what you bet, the leader has the ability to roughly match your bet and snare both the high and the low for this hand. Add to that a tournament rule that limits the time you are allowed to think before betting, and it can be tough to make a good bet. Fortunately, there’s a great shortcut that you can use to choose a bet size that maximizes your chances of passing the leader, without having to do a lot of calculations.

As usual, we’ll use some concrete examples here, so get ready to think a little. Let’s imagine our tournament allows betting limits of $5 to $1000, and we’re trailing the leader with $2000 in chips compared to his $2050. The good news is that we’re only $50 out of the lead. The bad news is that the leader can margin our bet easily, since we’re “on the button” and must bet first. The dealer is awaiting your betting decision, and time is running out. How can you decide the best bet size? If there are several hands to go yet in the round, it would be nice to take the lead here, but we don’t want to risk any more chips than are necessary to help the cause.

Since the leader can match your bet behind you, you can’t catch him with a single bet win unless he makes a betting mistake, or you get better cards. However, options for doubling, splitting, and blackjack all give you additional ways to overtake the leader. Let’s look at a few of these possibilities.

His optimal bet will likely be whatever you bet, plus almost all of his lead.

First, consider how much the leader can bet behind you. His optimal bet will likely be whatever you bet, plus almost all of his lead. If you bet $100, he can bet up to $149 and still have both the high and low. (For definitions of the “high” and “low”, see the previous article: Free Hits.)

You’ll overtake the leader if you win while he pushes or loses, and also if you push while he loses. That’s true anytime you bet at least your deficit plus a chip. However, your bet of $100 adds an extra way for you to win, that the minimal $51 bet does not provide. Let’s assume that he bets $149 behind you. Now, if you can win a double-down bet, you’ll overtake him even if he wins his hand. You gain $200, he gains $149, and now you have a $1 lead. That’s no coincidence. But, we can do better yet.

This time, you bet $200. He places an optimal bet of $249. You’ve just added an extra way to win. A double-down obviously still wins for you, but now look what happens if you draw a blackjack. A blackjack on your $200 bet pays $300. If he wins his $249, and you win $300, you’re $1 ahead again. Again, no coincidence there.

One more time, this time you bet $250. Your opponent bets $299. This time, he’s the lucky one, drawing a blackjack. You groan, but then push out the money to double on whatever hand you have. If you succeed in your double down, you win $500. The leader picked up only $448.50. You now lead by $1.50.

Each of these decisions involves several calculations, and going through this process at the table is clearly a problem. That’s where the shortcut comes in. You’re guaranteed to have these extra ways to win if you simply make sure you bet at least the following multiples of your deficit. In our example, we had a $50 deficit going into the hand:

  • Bet 2x your deficit ($100): You win with a double-down over a single bet win by the leader.
  • Bet 4x your deficit ($200): You win with a blackjack over a single bet win by the leader.
  • Bet 5x your deficit ($250): You win with a double-down even over a blackjack by the leader.

So, when in doubt, try to bet 5 times the deficit. If a bet that large endangers your position to other players at the table, consider betting 4 times or 2 times the deficit instead. Worst case, drop back to 1x plus a chip.

Sometimes these multiples overdo it, and a smaller bet will accomplish the same thing. If your bet is near or at the maximum, the leader won’t be able to bet much of his lead on top of the matching bet. Also, if betting must be in multiples of $5, sometimes these multiples overshoot the target by a little. But, the real beauty of this rule is its simplicity. It’s quick and easy to calculate, and you’re guaranteed to have the benefits described.

You’ll also often find that the leader will not make anywhere near an optimal bet behind you. They may bet too little, and give you extra ways to overtake them, or often, they’ll overbet and give you the low on the hand. Even though you have a considerable bet working, you might be pulling for the dealer to wipe out the table.

Of course, in each of these cases, the leader can double-down behind you to retake the high. But, hey, you’re trailing, on the button. Of course you’re an underdog! You have to make the best of your circumstances. Using the Rule of 2, 4, and 5 gives you an easy way to do just that.

See you at the tables, -Ken-

For more articles on blackjack tournaments and tournament strategy, you can:
Return to the Blackjack Tournaments Section, or
Move on to the next article Beyond Wong – A Few Tournament Tips That Uncle Stanford Never Told You.

About the Author

Creator of, very few can rival Ken's experience and knowledge of blackjack. His blackjack resume includes winning numerous tournament winnings, making several TV appearances and authoring multiple books on blackjack tournament strategy. Discover more about Ken's background and how he got started here

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