Counting Cards in Blackjack
Counting cards in blackjack is one of the only ways
to get an edge over the casino--i.e., it's one way of
playing blackjack profitably. The way that casinos
make their money is by setting up the rules of each game
in such a manner that they have an edge over the player.
Since the composition of a deck of cards changes as each
card is dealt, you're able to raise the amount you're
betting when the odds are in your favor, and lower the
amount you're betting when the odds are against you.
for money for yourself, and you'll quickly see why this is true.
That doesn't mean it's easy. If it were easy,
everyone would be doing it, and the casinos would have
no choice but to change the rules or eliminate the game.
They're never going to offer a game where the player has
a consistent advantage, just like a grocery store is
never going to sell groceries at a consistent loss.
Businesses are motivated by profit.
Why isn't it easy to get an advantage this way? There
are multiple reasons. One is that it requires a lot of
practice and skill to gain a small edge. So you have to
be smart and dedicated if you want to succeed, and you
also need a sufficient bankroll to be able to play long
enough for your small long-term advantage to kick in.
One of the other reasons is that casinos don't like card
counters. They'll kick you out of the game or out of the
casino if they think you're doing it. Another tactic
they'll use is to shuffle every hand in order to
eliminate the possibility that you'll get an edge.
Basic Strategy and the House Edge
learning this particular advantage gambling technique,
you have to learn something called "basic strategy".
This will come in handy even if you decide that counting
cards isn't for you. Basic strategy is the
mathematically correct play for every possible hand in
blackjack. Before you can tilt the odds in your favor,
you have to be able to reduce the house's mathematical
dominance over you. Memorizing and then using basic
strategy is how you do this. The house edge in blackjack
for a player who just guesses at how to play is around
4%. Basic strategy reduces that to 0.5% or so.
The house edge is the percentage of each bet that the
expects to keep over the long term. So if a casino game
has a house of 4%, the casino expects to keep $4 out of
every $100 that you wager. It's a statistical
probability that comes into play over an enormous number
An important thing to keep in mind about the house
edge is that if you're making wagers at a disadvantage,
you'll lose all your money eventually if you keep
playing. The higher the house edge, the sooner it will
happen, but it will still happen. The only way to
guarantee consistent winnings over the long term is to
play a game where you have the edge instead of the
Counting cards can give you that edge, but it won't
give you an edge unless you're making the right playing
decisions on each hand.
Some people learn basic strategy by memorizing a
chart, but I learned by memorizing how to play each
specific hand. You have a limited number of potential
hand totals, and the dealer has a limited number of
upcards, so basic strategy can be presented as a list of
rules for how to play each hand in each situation.
I've provided that list below, but it assumes that
you already know how to play the game. It also assumes
that you're familiar with the game's terminology. If you
don't know the difference between a soft hand and a hard
hand, then you'll have some more studying to do before
this site will become useful to you.
Also, the correct tactic for some hands changes based
on the rules variation can vary, but the rules below
will only be in error part of the time. If you want to
generate a more specific chart for a specific set of
rules, use the generator on Ken Smith's site,
The tactics for hard hands are easy to learn, and
that's where you should start. Remember that these are
the correct way to play HARD hands, not soft hands.
(Those hands are covered in the next section after this
- Always hit a total of 8 or less.
- Double down with a 9 IF the dealer's upcard is a
3, 4, 5, or 6. Otherwise, take a hit.
- Double down with a 10 UNLESS the dealer's upcard
is a ten or an ace. Otherwise, just take a hit.
- Double down with an of 11 UNLESS the dealer's
upcard is an ace. If the dealer has an ace, just
- Stand on a 12 if the dealer's upcard is a 4, 5,
or 6. Otherwise, hit.
- If you have a total of 13, 14, 15, or 16, you
stand if the dealer has a 6 or lower. Otherwise,
- If you have a total of 17, always stand.
Learning to play the soft hands correctly is actually
easier, because there are fewer potential situations.
The tactics for each possible situation follow:
- Double down with a 13 or 14 IF the dealer has a
5 or 6 showing. Otherwise, hit.
- Double down with a 15 or 16 IF the dealer has a
4, 5, or 6 showing. Otherwise, hit.
- Double down with a 17 IF the dealer has a 3, 4,
5, or 6 showing. Otherwise, hit.
- Double down with an 18 IF the dealer has a 3, 4,
5, or 6 showing. If the dealer has a 2, stand.
- Always stand with a 19 or higher.
If the casino's rules don't allow you to double down
in certain situation, take a hit instead.
Any time you get two cards of the same rank, you have
the option of splitting. If you don't split, then treat
the hand as the appropriate soft or hard hand.
- Never split aces or 8s.
- Always split 4s, 5s, and tens.
- Split 2s and 3s if the dealer has a 4, 5, 6, or
- Split 6s if the dealer has a 3, 4, 5, or 6.
- Split 7s if the dealer has anything lower than
- Split 9s if the dealer has a 2, 3, 4, 5, or 6 OR
if the dealer has an 8 or 9. Otherwise, stand.
By following the approach above, you'll reduce the
house edge so that blackjack is ALMOST an even odds
proposition. The rest of this page discusses how to get
Advantage Play and How Counting Works
Since basic strategy reduces the house edge to almost
0%, anything you can do to improve your odds starts to
tilt the odds in your favor. A card counter tracks the
ratio of high cards to low cards in the deck. This
enables her to improve her chances in two ways.
The first way is by adjusting her decisions based on
this new ratio. For example, if a deck of cards has a
lot of low cards in it, then it might be appropriate to
just hit a total of 11 instead of doubling down.
The second ways is by allowing the counter to
increase her bets when the composition of the deck means
she has an advantage. In a single deck game, the player
has an advantage over the casino about half the time.
That's because having certain cards in the deck
increases the player's odds, while having certain other
cards in the deck increases the casino's odds.
The best way to illustrate this is with an advantage.
If you were playing a blackjack game that paid 3 to 2
for a natural 21, and the deck had no cards in it but
10s and aces, you'd have a clear mathematical advantage,
because it would be easier to get the increased payout.
On the other hand, if you were playing in a blackjack
game where there were no aces at all, it would be
impossible to be dealt a natural, which would sway the
math more in the casino's favor.
In the first of those two hypothetical situations,
you would want to wager more money. In the second
situation, you wouldn't want to wager at all--at the
very least, you'd want to wager less.
Card counters increase the size of their bets when
the deck favors them, and they reduce the size of their
best when the deck favors the casino. If they're
proficient enough, they gain a long-term edge over the
Multiple systems are used by advantage players to
track the ratio of high cards to low cards in a
blackjack deck, but they all use a similar methodology.
Rather than memorizing the specific cards which have
been played, they assign a numerical value to the high
cards and the low cards. This running total provides an
approximation of how favorable the deck is to the player
or to the casino, and the counter adjusts her bet size
The most commonly used system is called the Hi Lo
system. The Hi Lo system assigns the following values to
- 2s, 3s, 4s, 5s, and 6s are worth +1
- 7s, 8s, and 9s are worth 0
- 10s and aces are worth -1
This is a balanced system, so if you count through an
entire 52 card deck, you're running total should be 0
when you finish. And in fact, this is exactly what you
should do in order to learn how to count--practice with
a single deck of cards at your kitchen table until
you're able to quickly deal through all the cards and
get a running total of 0 at the end.
Once you're able to do that proficiently one card at
a time, start dealing yourself the cards two at a time.
You'll notice that many combinations cancel each other
out. For example, if you deal a 10 and a 2 to yourself,
the net count for those two cards is 0.
In order to pull this off when you play
blackjack for real money, you need to be able to do this without
looking like you're doing it. You can't move your
lips. You can't look like you're concentrating. It has
to be so natural to you that the casino doesn't notice.
Most people will think they have the knack of it
sooner than they really do. That's because counting
cards in a casino is harder than doing so in the comfort
and quiet of your own home. For one thing, casinos are
loud and busy, which is distracting. For another thing,
you're being watched in a casino, and that will just
plain rattle some folks.
The Running Count versus the True Count
To make it harder for players to get an advantage,
casinos use multiple decks--sometimes as many as eight
decks at a time. This reduces the net effect that each
card has on the ratio of what's left in the deck.
For example, if an ace is dealt from a 52 card deck,
you have 3 aces left out of 50 cards. That's 6% of the
deck. But if an ace is dealt from a 416 card deck, you
have 31 aces left out of 414 cards. That's 7.5% of the
deck, which is a significant difference.
To compensate for the additional cards, you have to
convert your running count into a true count. You do
this by dividing the running count by your estimate of
how many decks are left in the shoe. You make your
betting and playing decisions based on the true count,
not the running count.
Bankroll Management and Bet Sizing
A flat bettor bets the same amount on each hand, no
matter what. Casinos are comfortable with flat bettors.
Counters, though, bet the minimum when the house has the
edge, then they raise their bets based on the count.
If you want to count cards, you should have a
blackjack of at least 100 times the minimum bet. That
means if you're playing the $5 tables, you need a
bankroll of at least $500. Having a large bankroll
reduces your chances of going broke because of a losing
streak. Advantage gambling is about accumulating a small
advantage over a lot of bets, because in the short term,
anything can happen, no matter what the odds are. The
actual results grow closer to the mathematical
expectation the longer you play.
When the count is negative or 0, you flat bet the
minimum bet. When the true count goes up, you raise your
bets accordingly. Most players range their bets between
one and four units, but an aggressive player might range
her bets between one and eight units. The size of each
bet corresponds to the true count. So if you have a true
count of +4, you'd increase you bet on the next hand to
four or five units to capitalize on the advantage.
Using this technique can change the house edge on a
blackjack game from 0.5% to 1.5% in favor of the house
to from 0.5% to 1.5% in favor of the player, depending
on the conditions of the game being played.
Is It Legal?
In the United States, things are legal unless a
specific law forbids them. As far as I know, no law
prohibits thinking during the playing of a game. I'm not
an attorney, but I'd be willing to go out on a limb and
say that counting cards is legal.
Is It Cheating?
The casinos think it is. Advantage gamblers don't
think so. It depends on your definition of cheating.
Since you're not modifying the conditions of the
game, you're not cheating under the legal definition.
Casinos, on the other hand, think that counting violates
the spirit of the game, so they consider it cheating. In
most jurisdictions, including Las Vegas, they have the
right to ban players from their blackjack games.
Atlantic City is one notable exception, but if you
play blackjack there, don't expect to find conditions that are
favorable to getting an edge. Since the courts ruled
that they couldn't bar players, they changed the rules
so that it's practically impossible to get an edge.
Can You Count Online?
simulates the same 52 card deck used in a brick and
mortar casino, can you use this technique to get an
advantage on the Internet? Theoretically, you could,
except for one wrinkle. Internet casinos use a random
number generator that shuffles the deck after every
hand. So the composition of the deck is entirely random
at the start of any new hand.
Real money online blackjack is a lot of fun, but it's not a beatable