All Blackjack basic strategy decisions are based on the up-card of the Dealer, hundreds of millions of hands have been analysed to arrive at the optimum way to play every hand a Player can get against every possible Dealer up-card. It is irrelevant to speculate what the Dealers Hole-Card actually is, blackjack basic strategy is based solely on the Dealers up-card and your hand.
Basic Blackjack strategy is the optimum way to play each and every hand you can possibly be dealt against all Dealer up cards. Basic Blackjack strategy is based upon scientific analysis of the game and this knowledge can dramatically increase your odds. Experienced Blackjack players divide Blackjack hands into two categories, the 'no-brainers' and the 'agonisers'.
The 'no-brainers' are hands that you don't have to think about. If you have a hard hand that totals 17 or more you will stand against all dealer up-cards. If your hand is eleven or less you should hit until you reach twelve or more. On some of these hands when appropriate you'll double-down.
Once you have a total of 12, 13, 14, 15 or 16, you now have a hand that requires thought. Do you stand or do you ask for another card? Hands that you have to ask yourself these questions are known as 'agonisers', these hands call for a player to make decisions, often painful ones. The hard hands of 12, 13, 14, 15 and 16 are hands where a player can bust if he hits and receives a card or combination of cards that make him go over 21. Some players foolishly never hit on these hands, these players are losing out because this strategy gives the casino a big edge.
Now let's take a closer look at hard hands.
When your hand totals 12, hit against a Dealers 2, 3, 7, 8, 9, 10 or Ace, until you reach 17 or more. Stand against a Dealers 4, 5 or 6. Many players hesitate to hit their 12 against a Dealers 2 or 3 thinking incorrectly that they should let the Dealer take a card in the hope that they will Bust, it's the wrong play. Hundreds of millions of simulations have shown us that optimum strategy for a 12 against a Dealers 2 or 3 is to hit.
If your hand totals 13, 14, 15 or 16, treat it the same way. Hit against a Dealers 7, 8, 9, 10 and Ace. Stand if the Dealer has 2, 3, 4, 5 and 6. If surrender is allowed, surrender your 15 against a Dealers 10 and your 16 against a Dealers 9, 10 and Ace.
No here is some strategy where you will be doubling-down. When your hand totals 9, you should double-down against a Dealers 3, 4, 5 and 6, hit against a Dealers 2, 7, 8, 9, 10 and Ace.
If you have 13 or more against a Dealers 2 don't take any more cards.
If your hand totals 10, double-down against a Dealers 2 though 9. Hit against a Dealers 10 and Ace until you get 17 or more.
When your hand totals 11, double-down against the Dealers 2 through 10. Hit against a Dealers Ace until you have 17 or more.
Now let's deal with basic blackjack strategies for soft hands.
Always keep in mind that when you hit your soft hand it will eventually become a hard hand, then follow the strategies for hard-hitting and standing.
Let's say you have a soft-13 or soft-14, you should double-down against a dealers 5 and 6. You should hit against everything else.
When you have a soft-15 or a soft-16 you should double-down against a dealers 4, 5 and 6. You should hit against everything else.
When you have a soft-17, double-down against a dealers 3, 4, 5 and 6, hit against everything else.
When you have a soft-18, double-down against a Dealers 3, 4, 5 and 6, stand against a Dealers 2, 7, 8 and Ace. Hit against a Dealers 9 and 10.
When you have a soft-19 or a soft-20 you should stand against everything.
The next area of basic strategy concerns what you do when you get a pair. Most casinos allow you to split your pairs and some casinos allow you to re-split if you receive a third and perhaps a fourth card of the same value. Wise pair splitting is money in the Blackjack players pocket. When you are dealt two Aces, always split them. When your dealt two 8s, split them also. Yes, you will even split your 8-8 against a Dealers 10 or Ace, however surrender an 8 against a Dealers 10 if surrender is allowed.
When you are dealt 2-2 or 3-3 split against a Dealers 2 through 7 and hit against a Dealers 8, 9, 10 or Ace until you get to 17 or more.
The hand of 4-4 is played in two distinct ways depending on the rules of the game you are playing. If the casino allows doubling-down after splitting pairs, then you should split 4-4 against a Dealers 5 and 6. You should hit against everything else. However, if the casino does not allow doubling-down after splitting you should simply hit this hand against all Dealer up-cards.
Now you are dealt 5-5, never split a pair of 5s, treat it as a 10 and double-down against a dealers 2 through 9. Hit against a Dealers 10 and Ace.
If you are dealt a 6-6, split against a dealers 2 through 6, hit against everything else.
If you are dealt 7-7 split against a Dealers 2 through 7, hit against everything else.
If you have a 9-9, split against a Dealers 2 through 6 and against a Dealers 8 and 9, stand against Dealers 7, 10 and Ace.
Never split 10s.
There it is, you now know everything you need to know to maximise your odds when playing Blackjack. It's a game where the proper standing, hitting, splitting and doubling-down decisions are necessary in order to cut down the house edge to a minimum. These rules are complicated, but take time to learn basic Blackjack strategy and you'll learn to win.