Blackjack Deck Estimation – Dividing Decks, Running and True Count

The dark art of counting cards at the game's table has always been a mainstay of many professional blackjack player's arsenal. But casinos have gotten wise to the practice. In order to mitigate the effects of counting cards, casinos have introduced both automatic shuffling machines as well as multiple decks for each game. This certainly throws a spanner in the works. Having said that, if you can master blackjack deck estimation, then you can move the odds ever so slightly more into your favour.

The dark art of counting cards at the game’s table has always been a mainstay of many professional blackjack player’s arsenal. But casinos have gotten wise to the practice. In order to mitigate the effects of counting cards, casinos have introduced both automatic shuffling machines as well as multiple decks for each game. This certainly throws a spanner in the works. Having said that, if you can master blackjack deck estimation, then you can move the odds ever so slightly more into your favour.

Blackjack Deck Estimation – Dividing Decks and the True Count

One of the most essential parts of card counting in blackjack is keeping up with the running count. The concept is simple enough and you need to be aware of the advantage that the remaining shoe contains, based on the cards that have already been played through. Knowing that is one thing about this. But an essential part is missing from your blackjack strategies. And that is the “blackjack deck estimation.” What we want to try and do is maintain the running count in blackjack and use it to your advantage. So we need to keep our eye on what’s called the “true count.”

Before we continue, we should point out that card counting doesn’t work with online casinos like King Billy Casino. Nevertheless, it’s still worth playing there as they offer all new players a bonkers welcome package of €1,000 to get you started.

Blackjack Deck Estimation and the True Count

When you’re learning how to play blackjack, providing you can maintain your concentration and focus, then keeping a running count is easy.

Once you have the basics down, then it’s just a matter of keeping practicing. Mind you, knowing how to apply the knowledge that you gained via counting cards is a totally different game. It’s not enough just to know the basics of the count, but if you can’t take advantage of this knowledge, then there’s little point in learning it.

How To Tell The Running Count From The True Count

First thing’s first. It’s important to be able to distinguish between a running count and the so-called true count. In truth, the true count is going to be more useful. This is because it takes into account the different characteristics that can be found when using multi-deck shoes. Though it sounds complicated, blackjack deck estimation is relatively easy to understand. Put in its simplest form, the true count is your running count divided by the number of decks in play. Now how do you go about figuring out exactly how many decks are in play? Well, that’s called blackjack deck estimation.

Let’s look at an example to give us an idea of how this functions. Imagine you’re playing a single shoe and you’re now more than 54 cards into the shoe. Also, your running count is a solid +14. Yes we know, this sounds bonkers on paper, but bear with us. Then imagine that there are still 7 decks to go. This would bring your card count down to earth with a solid bump giving you only a + 2, which is only a tiny advantage. Of course, this example presumes that you are playing a strategy like Hi-Low.

Blackjack Deck Estimation: The Number Of Decks In-Play

This brings up another very important factor. That is, exactly how many decks are currently in play? For example, imagine that you are 75 cards in. Of course, that’s more than one deck, though not quite two. But here’s the rub. Depending on how the numbers are rounded up, either up or down, can completely change your possibilities of how to win at blackjack. In this example, if you decide to round up, then you may start to play too conservatively and therefore lose out on any advantage you might have with counting cards. Conversely, if you round down, then you may unconsciously start to believe you have a bigger advantage than you have in reality.

If you talk to any blackjack professional gambler about this situation they will tell you that they simply divide decks into halves, quarters, or even eighths. In this case, counting every 27 cards would represent 0.5 of the deck. As Bill Kaplan might point out, there are many different approaches to playing and understanding blackjack estimation. We’ll try and list the ones we know about below.

Dividing Decks for Blackjack Card Counting

On the Whole, you’re going to find there are three common ways in which card counters divide the decks in any given blackjack shoe:

Full-deck division – increasing the true count divisor once for every 54 cards.
Half-deck division – increasing the true count divisor once for every 27 cards.
Quarter-deck division – increasing the true count divisor once for every 14 cards.

Accuracy Matters

On a technical level, it’s perfectly possible to find more accurate blackjack deck estimations. But dividing your running count with 0.25 numbers can prove quite challenging for most card counters. Now if you want to go even smaller, then you’re going to need to be a serious mental mathematics gymnast to be able to implement at the true count. Naturally, it goes without saying that the more accurate the division is, the better for your odds. The player advantage which you get by playing a Hi-Lo strategy is around 1% at most, according to most simulations. Keep in mind that this is if you’re playing a full deck running count along with perfect blackjack strategies.

Full Deck vs Half Deck Running Count

So let’s compare the full deck running count to that of a half deck running count. Straight away we’ll see that the latter offers a 6% better return. As far as the total player advantage goes, this translates to 1.06%. Right now you’re probably wondering whether it’s worth all that effort to keep track of those cards. We would say “maybe” because blackjack advantage play is really about gaining a tiny edge here and there.

If we dive even deeper into blackjack deck estimation and look at the quarter deck division, then we’ll see it offers a 7% better return than the full deck division. This translates to a 1.07% total power advantage, assuming of course you’re using your High-Low strategy, which in itself already offers a 1% player edge.

Blackjack Deck Estimation: Is it Really Worth All the Extra Effort?

Here at Blackjackchamp.com, we don’t really believe that counting quarters is worth the effort. Looking at it from a purely statistical point of view you can see that the extra advantage is negligible. On a practical level, all card counters are going to find it more difficult to divide quarters than divide whole or half numbers. You can try this by realizing how easy it is to divide a 0.5 on the fly. But now try, say 0.75. See what we mean. It’s not so easy. If you want to try it, then head over to King Billy Casino. They have over 100 live dealer games, including a huge number of blackjack varieties.

In summary, it’s important to realize that increasing the divisor in the true blackjack count formula to 0.5 for every 32 cards is probably the optimum solution. Not everybody is a maths prodigy. And may find it difficult to produce accurate estimations with smaller fractions. To that end, when you play online blackjack for real money, we don’t believe the extra effort for blackjack deck estimation is really worth it. For the best advantage, stick to what you know. As a given, you’re going to discover the hard way that virtually all modern casinos introduce new decks throughout the game. Coupled with shuffling machines, then the job of counting multiple decks is neigh-on impossible anyway. We suggest that you just make sure you play the perfect blackjack strategy.