Game Guides

Blackjack Strategy and Rules

On this page we outline the basics of blackjack including the rules and basic strategy, as well as more advanced methods such as card counting and shuffle tracking.

Blackjack (also called “21”) the Ace is worth 1 or 11, whichever is desired at the moment. All face cards (Jack, Queen, King) are worth 10 points, thus called ’10-count’ or “T” cards. All other cards are worth their number value. I.e., Q + 2 = 12. (Queen is a face card = 10; 2 = 2; thus the total 10 + 2 = 12.) The object of the game is to score as high as possible without going over 21. Therefore, 21 is the best score.

Every player starts with two cards, face up. The Dealer is dealt one card up (the “show” card) and one card down (the “hole” card). The players then go first, starting on the dealer’s immediate left.

If you want another card you say ‘hit’, if not you say ‘stand’. If you score 22 or more, you ‘bust’ or lose instantly. If your first two cards are a face card with an Ace, that is ‘Blackjack’ and you win instantly, plus a ‘Blackjack bonus’ of 50%. (I.e., if you bet $10, then with a ‘Blackjack’ you win $15.) After the players are finished, the dealer draws until he reaches at least 17, then he must ‘stand’.

Β Betting options

  • Splitting.
    If your first two cards have the same value, such as 8-8, you can “split” this into two hands, each hand starting with one 8 plus a second card from the dealer. If you split A-A, each new A-hand is not allowed a third card. A-A nonetheless is a good hand to split because you are likely to score 21 at least once. However this is not a ‘Blackjack’ so the dealer can achieve a tie if he also reaches exactly 21.
  • Doubling Down.
    Before drawing a third card, if you feel the dealer has a weak hand, you can double your bet. You then must take a third card, and are not allowed more cards. Usually, you are allowed to double down only if you have 9, 10, or 11. Sometimes, you can not double down on 9, and this lowers your advantage. Other times, you can double down on any two cards. This raises your advantage because sometimes it is good to ‘soft-double’ when you have A2, A3, A4, A5, or A6. (See the chart below.)
  • DAS or ‘doubling after splitting’.
    Sometimes this is allowed, sometimes not.
  • ‘Soft’ hands.
    A soft count or a soft hand is when you have an ace with a numbered card or cards below 10. For example Ace + 4 is a “soft 15” because it can be either 15 or 5.
  • Insurance.
    If the dealer shows Ace, you can buy insurance for half your bet-then you win instead of losing if the dealer has Blackjack. However this is never worthwhile. You are betting $1 to win a possible $3, for a ratio of 4:12. Meanwhile the ratio of Blackjack-making face cards (10, J, Q, K) to all other cards is 4:13. This is like playing a double-zero Roulette-type game with only 13 numbers per zero instead of the usual 18-and double-zero roulette already is a terrible game for the player, so go figure.
  • Surrendering.
    If your hand is terrible, you can ‘surrender’ if this is allowed. Then you only lose half your bet, but you always lose. Surrender is very helpful if you do not over-use it.Notice that about 1/3 of the deck is face cards and 10’s. So if you assume the dealer’s hole card is a 10-count, and draw or stand accordingly, then usually this results in ‘basic strategy’. Also notice that the dealer is weakest when he shows a 6, because he must hit and is very likely to bust. With 4 or 5 showing the dealer also is weak, but slightly less likely to bust.

Basic Strategy. To maximize your long-range chances to win playing online casino blackjack, you must make every decision according to a disciplined ‘basic strategy’. This was determined decades ago using computer analysis.

Basic Strategy for Online Casino Blackjack

Blackjack 21 cardsBasic strategy will minimize the casino’s advantage in land-based and in online casino blackjack. Below is a ‘universal’ basic strategy, modified very slightly for simplicity. There are more precise variations that require you to change according to the different rules of each casino. However for online blackjack, this is more trouble than it is worth because the improvement in results is not very significant. Print this universal strategy sheet and follow it whenever playing Blackjack at an online casino.

When to hit :

  • Hit hard 8 or less – always
  • Hit hard 9 – if dealer shows 2, 7, 8, 9, 10 or A
  • Hit hard 10 – if dealer shows 10 or A
  • Hit hard 11 – if dealer show A
  • Hit hard 12 – if dealer shows 2, 3, 7, 8, 9, 10, or A
  • Hit hard 13, 14, 15 or 16 – if dealer shows 7, 8, 9, 10, A
    (Exception – Stand/surrender with 7+7 against 10 in one-deck games.)

When to split :

  • Split 2’s & 3’s – if dealer shows 4-7
  • Split 6’s – if dealer shows 3-6
  • Split 7’s – if dealer shows 3-7
  • (Stand/surrender with 7’s against 10 in one-deck games.)
    Split 8’s – always
  • Split 9’s – if dealer shows 2-9, X-not-7.
  • (Split 9’s vs. 2 through 9, except not vs. 7.)
  • Never split 4’s, 5’s, or 10’s.
  • Spilt A’s – always

Always split Aces and 8’s, unless surrender is allowed. Then surrender with 8’s against a dealer showing a 10.

Hitting a soft hand:

Always hit a soft hand until you can score 18 or better, unless the strategy tells you to double down. If the dealer shows 9, 10, or A, then hit until you have 19 or better.

Soft 17 is not worth keeping, it beats nothing except a dealer bust. The risk of hitting is you may draw 8 or 9′ for a ‘hard’ total of 15 or 16 which you are likely to bust. Nonetheless, you cannot win every hand. In the long run this is well worth the risk.

When to surrender:

  • Surrender with hard 15 if the dealer shows a 10.
  • Surrender with hard 16 if the dealer shows 9, 10 or A.
  • If surrender is not allowed, hit or split according to basic strategy.
  • Surrender or stand with 7+7 against 10 in one-deck games.
    Otherwise, never surrender.

When to double down:

  • Double with 9 – if dealer shows 3-6
  • Double with 10 – if dealer shows 2-9
  • Double with 11 – if dealer shows 2-10

Doubling down with a soft hand:

  • Soft-double with A2, A3 against 5, 6.
  • Soft-double with A4, A5 against 4, 5, 6.
  • Soft-double with A6, A7 against 3, 4, 5, 6.

Soft-doubling may seem precarious, because you are only allowed one more card. Often this will be a 10, sticking you with a worthless score such as ‘soft 15’, etc. However, computer simulations prove that in the long run, when the dealer is weak, soft-doubling makes a lot of extra money for the player. The strategy is easy to remember if you note that (a) it relates to sets of two pairs, and (b) the two soft pairs A4, A5, include 4 and work against a dealer’s weakest cards down to 4. So just remember, A4, A5 against 4,5,6, – and the rest is easy. The next lower set of soft-doubling hands A2, A3 is weaker for the player, so we remove the doubling down against 4 where the dealer is not quite so weak. The next higher setΓ― A6, A7 is stronger for the player, and so we add the doubling down against 3.

When to buy insurance:

Never. Insurance is a sucker bet. The house advantage for insurance is similar to the house advantage for a slot machine-so it defeats your purpose of playing Blackjack.

Notice that about 1/3 of the deck is face cards and 10’s. So if you assume the dealer’s hole card is a 10-count, and draw or stand accordingly, then usually, this results in a pretty good “basic strategy”. Also notice that the dealer is weakest when he shows a 6, because he must hit and is very likely to bust. With 4 or 5 showing the dealer also is weak, but slightly less likely to bust.

Other, more complex strategies can be used for the seasoned veteran of the Blackjack table, but it is of importance to realize that none of the more advance methods of determining when to make certain plays or moves, can be used without a base knowledge of the basics.

Advanced Strategy of Counting Cards

The underlying principle behind card counting is that a deck will either have lots of tens (Kings, Queens, Jacks or 10s) and aces, called ‘a rich deck’ which is good for the player, or will have a deck rich in small cards, which is good for the dealer. The reason behind this principle is rather complicated, but I will try to offer two examples of why it is so important:

  1. Blackjacks are more common in ten and ace rich decks, (because 10 + 11 = 21!) which benefits the player more than the dealer.
  2. Β The probability of busting a stiff hand is greater. The dealer is forced to hit a stiff hand and the player is not.To gauge the richness of the deck in good cards, the player needs to keep track of the cards that have already been played.”But how?” you may ask. “After all, there are often several decks being played and I don’t have the mind of an elephant!” There are several strategies, one of which is a Plus/Minus strategy, which deals in positive and negative integers that anyone with ninth grade math can use as far as the math itself is concerned.

    However, the trick is keeping up with all cards played, and adding/subtracting at that rate.This system assigns a value of a positive number to 2, 3, 4, 5, 6 and, and -1 to tens and aces. Everything else is considered a 0 (zero), or neutral. At the beginning and end of a deck or ‘shoe’, the count is 0. Imagine a line with a zero in the middle and all the plus numbers to the right and the minus numbers to the left, on either side; just as a number line is math would be. As cards are played, the counter constantly adds and subtracts from the count accordingly. This running total is called the “running count”.


A game begins at zero and the first card is a 6. The counter thinks “+1”. The second card is a Jack (10). The counter thinks +1-1 = 0 Third card is a duce, (+1) making the number remaining a +1. Fourth card is an Ace, making the equation +1 -1 = 0 and so on.
At any time, a positive count means that a disproportional number of small cards have been played which means the deck is rich in large cards.

To determine the “true count” divide the running count by the number of decks left to be played, or in some strategies the number of half decks. This will tell you the relative richness of the deck in good cards.

Card Counting in Online Casino Blackjack?

Because the deck(s) of cards used for online casino blackjack is shuffled between each hand card counting is not possible. Each hand is an independent event, just like every spin of the roulette wheel is an independent event in a land-based casino. However, if you find a game where the software does not simulate a shuffle between each hand card counting would theoretically be possible, and in the early days of online gambling there were people taking advantage of these kind of opportunities.


By Simon

One of the first editors of Honest Casinos, I have been reviewing casinos since 2003.