BBC - h2g2 - Blackjack - the Card Game

The most common gambling card game worldwide, Blackjack¹ can be found in virtually every casino or gaming room you care to name. Its origins are lost in the mists of time; the French claim it as their own, a variation of chemin de fer, as do the Italians, a bastardisation of the more elaborate 'Seven and a Half'. Whatever the history, the game is renowned today as a standard pastime in today's casinos. The losses are rarely higher than the gambler can afford, and the wins, while modest, are more frequent than on the other tables.

The Basic Concept

Suits are irrelevant in blackjack, where the aim is to score 21, but not above. Cards 2-10 score their face value. The picture cards (Jack, Queen, King²) are also worth ten points apiece, and Aces score one or eleven at the discretion of the player. Each player places their bet ('stake') in a 'box'³ on the table and is dealt two cards, face up. The dealer is also dealt one card, again face up. Each player in turn may then request more face-up cards, one by one. At any point, if a player is satisfied with his cards, he can 'stick' with the hand, and play passes on to the next player⁴. If any player draws cards which put his total above 21, then he is 'bust', and his stake is lost to the dealer.

After all players have either stuck or bust their hands, then the dealer draws to his one card. The dealer is constrained by the house rules, however: if his hand scores 17 or above, he must stick, otherwise he must draw⁵. Any player scoring higher than the dealer receives a payout of 1:1 (if they bet �5, then they receive their stake back and an additional �5); players on the same score as the dealer receive their stake back. If the dealer busts then, of course, all players who have not also bust are winners. It will be noted from this that each player plays solely against the dealer; other player's hands are irrelevant to how much money you win or lose - a common misconception among amateurs.

The Interesting Bits

Casino blackjack has a few more variations than the average home game of pontoon⁶. These take the following forms:

Blackjacks - Any player being dealt an ace and a ten is said to have received a 'blackjack', which automatically pays out at 3:2 odds (if the bet was �5, then they receive their stake back plus an additional �7.50).
Splitting - Nominally, if you receive any two cards of the same rank (ie two threes, two Jacks, etc), you can request to split them. This is done by separating them on the table, and laying down a second bet, identical to the first, for the second hand that you have just created. Play then proceeds as normal. However, in Britain (and increasingly in the US), it is now forbidden to split fours, fives or tens. Why? Well, two fours add up to eight, so there is a good chance you will end up with a good hand anyway (see 'Analysis of Cards', below). Two fives add up to ten, which is a good hand to double down upon (see below), and two tens add up to 20, which more often than not is a winning hand. Unusually for a casino ruling, this actually benefits the player, and is enforced simply to save time. It is advisable to split 8s and aces (when you split Aces, many casinos will let you draw only one card to each, by the way, so check), but otherwise the decision is a largely arbitrary.
Doubling Down - When you have a hand that totals nine, ten or eleven points you are permitted to double down. This entails doubling your initial stake for the receipt of one more card only. It is generally a good move to double down hands on ten and eleven, given the number of cards worth ten points in the shoe⁷.
Insurance - This is more common in the US than in European casinos. If you draw a blackjack and the dealer's card is an ace, then you may be offered an insurance (usually half your original bet) against the dealer also drawing a blackjack (when you would only receive your stake back). If you take the insurance and the dealer does get a blackjack, then you are paid only at 1:1, not 3:2. It does not take a lot of maths to work out that buying insurance is not generally a good deal, although it can pay off if you are card counting (see below), and there are a lot of tens left in the shoe.

NB - Do not expect a pay-out for a five-card trick (in British or American casinos) or three sevens. These gimmicks are strictly for kids only (see footnotes).

Analysis of Cards

Ordinarily if you play exactly like the dealer, drawing on 16 and sticking on 17, you will lose, on average, 8% of your money. You can decrease that to somewhere around 6% with judicious use of splitting and doubling down. If you want to start winning money, however, you need to pay attention to a few things:

Dealer's Card

So many people profess to be able to play blackjack, but yet do not take note of what the dealer's card is. Remember the game is played against the dealer, and although you cannot predict his total, it is possible to predict when he is more likely to go bust. If the dealer has a low card, then the chances are that he will have to draw three or four more cards to exceed 16, therefore the chances that he will go bust will increase dramatically. Conversely, if the dealer's card is a ten, then there's a good chance (4 in 13, or about 1 in 3) that he will draw another ten, making an extremely good hand next time around. Hence:

If the dealer has less than a six, then you should stick on a hand as low as 12 or 13.
If the dealer has a six then you should stick on 14 or 15.
If the dealer has a seven or eight, stick on 16.
If the dealer has a nine or ten, then you should stick on 17. It seems ridiculous to twist on 16, but the odds do actually favour you.

Obviously, it is never worth sticking on less than 12, as no card in the pack will bust you. But remember that there are 96 cards worth ten points in a full shoe, so every time you draw to a twelve or more you are taking a gamble.

Card Counting

In theory, it has been proven that the human brain can comfortably remember 312 cards. However, the work involved does tend to detract from the average casino visit, so there is a simpler method to use and not wrack your brain too much:

Starting from the beginning of a new shoe, note each time any of the following cards is dealt (to anyone around the table, including the dealer), and count accordingly: All twos, threes and fours (-2), all tens (+1), all aces (+2). The card count will generally be positive, but if you find it is negative towards the end of a shoe, then you know that there are a lot of big cards remaining, which bodes well for someone to get a black jack on the next couple of hands. You may want to increase your bet, or consider taking insurance on the strength of this. This scheme works best with four- and six-deck shoes, the most common sizes in UK casinos.

Warning! This, like all gambling 'schemes', is by no means a guarantee of a win. In addition, many casinos, especially in the US, tend to frown on anyone who is visibly seen card counting. If you are not discreet, then you may be asked to leave the premises.

And If I'm Still Not Sure?

Blackjack is one of the most acceptable games to 'back' other players. If your chosen table is full, or you want to experience the thrill of gambling before sitting down and losing your own money through a serious of beginner's errors, then you can back a player already on the table simply by placing your bet behind the player's own in the box. Your bet does not have to match his, it simply has to be, like all bets, within the minimum and maximum of the table.

It is obviously advisable to back someone who looks as if he knows what he is doing, is not drinking alcohol, and who is not making either huge profits or losses. It is, of course, courteous to ask the player if they mind being backed, and very churlish of the player to refuse. In a well-known incident, a casino cheat refused consistently to be backed, for fear of drawing attention to himself, and was collared by Security on the basis of that alone. But do not worry, if you back a cheat, most casinos will refund your money out of the winnings they have confiscated from him.