My favorite reference on the subject of blackjack odds is Mike Shackleford at http://www.wizardofodds.com/ . He talks about card counting a bit. I trust what Mike Shackleford has to say on the subject, so definitely read him.

My feelings on card counting are:

- It doesn't make a huge difference in your return. Only fractions of a percentage.
- It is only really useful for single deck play, which is becoming more and more rare.
- In the casinos I frequent, the only remaining single deck games are the new "blackjack pays 6 to 5" games, which is a new rule that tips the odds farther into the casino's favor, counteracting the advantage that card counters have.
- The good card counting systems require too much concentration and take the fun out of the game.

With that said, I frequently play single deck 6-to-5 games and I do sort of keep eye on the basic ratio of tens, just as a way of getting a feel for when to bet higher.

More details:

I learned what's called the "unbalanced tens count". This is not a particularly powerful counting system, and it's not hugely accurate, but it is easy to learn and does not require much concentration, so it doesn't detract from the fun of the game. It works like this...

A deck that is rich in tens and face cards (face cards have a value=10) is beneficial to the players, a deck that is poor in tens and face cards is beneficial to the dealer. So. If the dealer is getting ready to deal, and the deck is rich in tens, then you can bet higher on that hand.

The reason: A dealer must hit on a stiff hand, whereas you don't necessarily have to. The idea is, you want to get into situations where the dealer's cards are a ten and a small card like 2 through 6. Then, because the deck is rich in tens, the dealers next hit is more likely to be a ten and therefore bust the dealer. You, on the other hand, can stand on your lower hand and let the dealer bust. So you win without having to take a chance and hit a stiff hand.

(But since all you're doing is keeping track of the ratio of tens, this is an iffy proposition. Even with a deck that is rich in tens, the dealer can still show a 16 and draw a five. It's just a tad less likely. So you will win and lose with counting, just like you win and lose without it. The ratio of wins and losses will be the same, but since you're betting higher on the times when the dealer is a tad more likely to bust, your overall win amounts will just be a slight fraction higher if you're counting.)

What makes the simple "unbalanced tens count" useful in single-deck play is: At a crowded casino, with all of the seats at a single deck table filled up, you usually get only two hands after a shuffle before another shuffle is needed. So you really don't even need to keep a running count in your head, you merely need to know what the 10s ratio was on the last hand, the one right after the shuffle. So it's really easy to do. The pattern goes like this:

The dealer shuffles.
You bet low.
Watch the cards in that hand.
Did a disproportionate number of little cards come out on that hand?
If so, bet high on the next hand. If not, bet low.
The next hand is dealt, it plays out, etc., hopefully you won it if you had bet high.
Now it's time for another shuffle.
Repeat.

Okay, so that's the basic pattern. The actual unbalanced tens count works like this.

- Every tens-value card (10 J Q K) offsets two little cards (A 2 3 4 5 6 7 8 9)

- Each tens-value card that gets dealt is bad, and is worth negative two. Each little card that gets dealt is good, and is worth positive one.

- So for every ten that is dealt, if there are two corresponding little cards being dealt also, then those are a "wash" and the count doesn't change. For example, if there are eight little cards on the table, and four tens on the table, the ratio of tens to littles hasn't changed. But if there are eleven littles and four tens on the table, then the ratio has changed, in your favor (positive), by three.

- Now, notice in each suit there are four tens (10 J Q K) and nine littles (A 2 3 4 5 6 7 8 9). Nine divided by four is not two, there's a remainder of one. So technically, each ten does not really exactly offset two littles. That's where the "unbalanced" part of the "unbalanced tens count" comes in. When you start a fresh shuffle, the count is actually unfavorable by one card per suit, or four cards in the total deck. So on a fresh shuffle, your count starts off at negative 4. Only when the count ratio has changed, in your favor, by more than four, can you start to think about betting high on the next hand.

- And actually, you only want to start betting really high if the ratio is particularly favorable. Like, +4, +8, or more.

- For instance, if you just saw a hand that was almost all little cards and only a couple of tens. Let's say the dealer just shuffled, and you just watched the other five players at the table just hit hit hit hit like crazy because they kept getting twos and threes and such, and the dealer hardly dealt any tens to any of them. Before the dealer sweeps up all the cards off the table, you can see what's out there and get a basic idea of what the ratio was. You can go "wow, look at all those little cards" and then put some extra chips in your betting circle.

Thats' really all that counting is, for me. Not a detailed science, just a basic feel for how much more likely the dealer will be to bust on the next hand.

Anyone else want to share their counting systems?

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