The 10 Basics of Blackjack Strategy

Most people know that blackjack strategy is a real thing. They might also think that slot machine or craps strategy is a real thing, too, but they’re right about the former and wrong about the latter.

Why is that, though?

Why does blackjack have a strategy when games like roulette and craps don’t?

The main reason is that you make decisions about how to play your hand in a game of blackjack. These decisions have a direct effect on how much you win or lose.

Here’s an example:

Most people understand that a total of 22 or higher is an automatic loser in blackjack.

Suppose you have a hard total of 20. (That’s usually 2 cards worth 10 each.) If you take a hit in this situation, the only card that WON’T bust your hand is the ace.

The only possible values for cards in blackjack are 1-11, inclusive. The ace is the only one that won’t bust your hand.

How likely are you to get an ace in this situation?

It doesn’t take a rocket surgeon to understand that it’s only about 1 in 13.

If you hit a hard total of 20, you’ll bust 12 times out of 13.

That’s bad strategy.

But blackjack strategy gets more complicated when you start dealing with more interesting totals. Also, you must take into account the value of the dealer’s face up card when deciding how to play your hand.

Here are the 10 basics of blackjack strategy that everyone should learn:

“Basic strategy” in blackjack is a specific phrase with a specific meaning. It’s a rubric that explains how to play every total in every situation. If the basic strategy in question has been created correctly, it offers the best mathematical expectation in all those situations.

The house edge is the estimated average amount you’ll lose every time you bet on a casino game. In blackjack, if you’re playing with perfect basic strategy, the house edge hovers around 0.5%. This percentage changes based on the specific game rules in your casino.

If you deviate from basic strategy, the house edge increases. The average blackjack player faces a house edge of 4% to 5% because they don’t understand or use basic strategy.

It’s easy to estimate how much money you’ll lose per hour playing blackjack. You just multiply the house edge by your average bet size. Then multiply that by the number of hands you’re playing per hour.

If a perfect basic strategy player gets in 100 hands per hour at $5 per hand, she’s putting $500 into action. If the house edge is 0.5%, she’s expected to lose $2.50 on that action.

On the other hand, the average player would expect to lose $25 on that action.

That’s a big difference.

Most people can memorize basic strategy in an hour or two if they’re willing to put in the effort.

You only have 2 real pieces of data to work with when determining the correct play in a blackjack hand:

• 1. Your total
• 2. The dealer’s face up card

A basic strategy chart lists your possible totals on the left vertically, and it lists the possible dealer up cards across the top of the chart horizontally. Compare your total with the dealer’s up card, and the chart explains whether you hit, stand, double down, or split.

These charts are usually color-coded to make them lose. You can buy a basic strategy card in the casino gift shop, and it’s usually accurate—at least for the game, it was written for.

Generally, you’ll play more aggressively (hit more often) when the dealer has a 7+ showing. When the dealer has a 6 or lower showing, you’ll be more likely to stand.

This is because the dealer is more likely to bust a hand with a 6 or lower in it.

Of course, this also varies based on your total. You’d never stand on a total of 11, because the probability of getting a 10 on your next card is relatively good compared to the odds of getting any other total.

In fact, you can a hit a total of 11 without worrying about busting. The highest value card in the deck is a 10 in this situation, which gives you a perfect total of 21. (An ace can be worth 11, but since it can also be played as a 1, it doesn’t warrant mentioning here.)

When you’re looking at a blackjack hand, it can fall into one of the following categories:

• 1. Hard totals
• 2. Soft totals
• 3. Pairs

A hard total is any hand without an ace. It’s also a hand with an ace in it where the ace must be counted as 1 to avoid busting.

A soft total is any hand with an ace where the ace can be counted as 1 or as 11. Generally, you’ll play soft hands more aggressively than hard hands.

A pair is a hand where both cards have the same ranking. You can “split” a pair into 2 new hands by placing an additional bet. Each of the 2 cards in your original hand becomes the 1^st card of a new hand. Those 2 hands are played separately.

When you’re deciding how to play your hand, the first decision to make is whether to split. If you don’t have a pair, this isn’t an option anyway. Once you’ve decided whether to split, you move on to decide whether you have a hard hand or a soft hand.

Based on your total and whether it’s hard or soft, you’ll take the action which has the best mathematical expectation for you.

Some hands are so bad that the mathematical expectation is negative no matter what action you take. In that case, the best possible play is the move with the lowest negative expectation.

It doesn’t take a lot of memorization or skill for a lot of the basic strategic decisions you need to make. Here are some examples of easily remembered decisions you might need to make:

• 1. Always split aces and 8s.
• 2. Never split 4s, 5s, or 10s.

That’s half the possible ways you can have a pair, by the way. If you can memorize those 2 lines, you know 50% of the basic strategy for splitting pairs already.

Here are some additional easy to remember basic strategy plays:

• 1. Always stand on a hard total of 17 or higher.
• 2. Always hit a hard total of 8 or less.
• 3. Always stand on a soft total of 19 or higher.

Those are some of the basics, but here are a couple more:

• 1. Always double down on a total of 11 unless the dealer is showing an ace.
• 2. Always double down on a total of 10 unless the dealer is showing a 10 or an ace.

Those are the basics of doubling down, and they cover a lot of situations, too.

If you have a hard total of 12, 13, 14, 15, or 16, you have a tricky hand. That hand stands a good chance of busting.

The deciding factor for how to play those hard totals is the dealer’s up card.

If the dealer has a 7 or higher, you’ll hit those totals. The chance that the dealer has a 17+ in that situation is high enough that it’s worth the risk of busting to try to get a better total.

If the dealer has a 6 or lower, you’ll stand on those totals. (Except if you have a 12 and the dealer has a 2 or 3.) The reason you stand is because the dealer has a good chance of having a hand she’ll have to hit and will likely bust.

That’s most of your hard totals strategy right there.

I already talked about a hard total of 10 or 11 and when you should double down on them. Now let’s talk about a hard total of 9.

You’ll double down on this total if the dealer has a 3, 4, or 5. The dealer has a good probability of busting, AND you have a good chance of improving to 19. This is a good position to be in, so you want to capitalize on it by getting more money into action.

I’ve covered all the possible decisions for hard hands already, and I’ve only written half this post.

See how easy blackjack basic strategy is?

You have a lot more options with soft totals because of the flexibility they offer. You’ll double down on certain soft totals, hit other soft totals, and you’ll stand on only a select few of the soft totals.

And the dealer’s up card still affects your decision.

With a soft 17 or 18, you’re likely to be in a situation where you can double down. If the dealer has a 3, 4, 5, or 6 showing, you’ll double down on such a total.

There’s a good chance when doubling down on one of those totals you’ll wind up with and 18 or 19 (or at least a 17 or 18). Combine that with the possibility of the dealer busting, and you’re in a great situation where you want to get more money on the table.

With a soft 15 or 16, you’ll only double down if the dealer has a 4, 5, or 6 showing. If the dealer has anything else showing, you’ll hit this total. (But you won’t be as nervous about it as you would if it were a hard 15 or 16, because you won’t bust with a soft total.)

With a soft 13 or 14, you’ll limit your doubling down to when the dealer has a 5 or 6. You’ll hit in any other situation.

And that covers all the soft totals, now, too.

I already explained that you’ll always split aces or 8s. The reasons for this should be obvious, but I’ll explain them anyway.

A pair of ace is also a soft total of 12. That’s a great hand, and you can do a lot with it.

But who wouldn’t want 2 blackjack hands, both of which started with an ace?

After all, there are more 10s in the deck than any other value. If you have 2 hands starting with aces, you have a good chance of winding up with a total of 21 on each of them.

A pair of 8s, on the other hand, is also a hard total of 16. No matter how you play a hard 16, you’re fighting an uphill battle. You’re likely to go bust, and even if you stand, the dealer’s likely to have a better hand than you.

But if you have 2 hands starting with an 8, you have a good chance of winding up with hard totals of 18 in each of the 2 new hands. That’s a respectable total and will often beat the dealer, no matter what.

I also wrote that you should never split 4s, 5s, or 10s. Here’s why:

A pair of 4s is the same thing as a hard total of 8. That’s not a bad starting total. If you get a 10 on your next card, you have an 18.

On the other hand, if you split that, you have 2 new hands, each of which has a starting total of 4. If you get a 10, your total is 14. That’s a total where you’re likely to bust.

Similar thinking applies to a pair of 5s, but think about this difference.

A pair of 5s is a hard total of 10. You’re likely to get a total of 20 or 21 with this starting hand. Even if you don’t, you have a good chance of winding up with an 18 or 19.

But if you split those 5s, you have 2 hands starting with a value of 5. Get a 10, and you now have 2 hands with totals of 15. Again, a total of 15 is hard to play—it’s going to bust as often as not. If you stand on a hard total of 15, the dealer is likely to just have more points than you.

Those are the easy ones, and I wanted to make sure you could follow the reasoning behind playing them this way. It boils down to the large number of 10s in the deck.

A 52-card deck of cards has 16 cards worth 10 in it. That’s 31% of the deck.

Some blackjack strategy pages suggest that you’re most likely to get a 10 on your next card than anything else. That’s not true. More than 2 out of 3 times, you’ll get something other than a 10.

But a lot of the cards you might get are similar to 10 in value. 8s and 9s often are almost as good as 10.

Let’s talk about 9s first. You’ll often, but not always, split a pair of 9s. After all, 2 hands that start with 9 are likely to turn into almost unbeatable totals of 19 each.

If the dealer has an ace or 10 showing, you will stand, though. She has such a good chance of winning in that situation that you don’t want to put more into action. You’ll also stand if the dealer has a 7 showing.

You’ll often split 7s, but not always. It depends on the dealer’s up card. If the dealer has a 7 or lower showing, split the 7. Otherwise, hit.

Pairs of 6s are similar to pairs of 7s. You’ll split if the dealer has a 6 or lower. Otherwise, you’ll hit. (The 7 up card is the only different situation.)

And you’ll play pairs of 2s and 3s exactly like you’d play a pair of 7s.

So that’s easy to remember, too.

Want to know how and why counting cards changes basic strategy?

That starts by understanding the basic concepts behind card counting.

One of the unique things about blackjack games is that the odds change as the cards are dealt. Imagine playing a roulette game where slots got filled in after they were hit. It’s easy to see how that would change the probability behind the game.

That happens in blackjack, too.

When you’re dealing with a deck of cards in blackjack, you’re dealing with a deck that has an equal number of high cards versus low cards at the start of the game. As the cards are dealt, standard deviation creates situations where the number of high cards versus the number of low cards changes.

Why does this matter?

A blackjack (or a “natural,” if you prefer) pays off at 3 to 2.

And if you have proportionally more aces and 10s in the deck than low cards, your probability of being dealt that hand increases.

Most card counters get their edge over the house by raising the size of their bets when the deck is “favorable”—rich in 10s and aces.

But that change in the composition of the deck changes the probabilities elsewhere in the game, too.

According to Blackjack Forum Online, you have 16 basic strategy situations that are most important to card counters. These are:

With those hands, depending on the count, you’ll deviate from basic strategy. These basic strategy deviations increase your edge against the house even more than it would increase by just raising your bets when the count is favorable.

Not all blackjack games are created equal. Casinos vary the rules and standards for play. The main rules changes that affect basic strategy are these:

• The number of decks in play is the first one. Basic strategy changes when you’re playing in an 8-deck game when compared to a single deck game.
• Whether the dealer hits or stands on a total of soft 17. This rules change also has a major effect on the size of the house edge.
• Which hands you’re allowed to double on has an obvious effect. In some casinos, you’re only allowed to double down on a 9, 10, or 11. In others, you can double down on any total. Clearly, if you can’t double down in some situations where basic strategy calls for it, your strategy has to be different.
• Whether you’re allowed to double after splitting is another factor. Obviously, it’s better for the players to have the option of doubling after splitting.
• Surrender conditions matter, too. Some casinos don’t allow surrendering at all, so it’s not an option. Others allow you to surrender early or late.
• When the dealer looks at her hole card is the final factor affecting basic strategy. In the United States, the dealer looks at her facedown card. In Europe, this isn’t done. This affects the correct strategy decisions, too.