blackjack math

The Zen Guide to Blackjack Math

Let's explore the mathematics of blackjack and learn how to use math to win at blackjack with an instructional video from Carleton University.

The object of blackjack is simple - get your cards to add up to 21 (without going passed 21) before the dealer. You do this by "hitting" or "sitting" - either getting a new card or keeping the ones you have if you think the other players will go over 21 or will not get as close to it as you have.

Considering the standard 52-card deck that plays the face value of the 2-10 cards, "face cards" (Jack, Queen, and King) are valued at 10 and the ace is either either a one or eleven - but the ace automatically becomes a 1 if the t\al value of the cards drawn add up to over 21. In this game, suits do not matter.

The important stuff. A "Blackjack" is a hand that equals 21 in two cards - the best hand to get - a 10-valued card and an ace.

Before the Math: a Short Blackjack Wiki

Before we get into strategy and the art of blackjack math, there are a few more terms we need to discuss.

Once the dealer has set out the first cards, the player has several options:

  • Hit - Get another card.
  • Stand - Just keep the cards you have and take no more.
  • Double Down - Your bet has now doubled in value and you will receive one more card only. Never double down on a 20.
  • Split - If you have drawn a pair, you can split those cards into two separate hands. Remember, you always want to split aces and eights because aces have the helpful duality of valuing either 11 or 1 and two eights equals 16 which is one of the hardest hands to win off of.
  • Surrender - In some casinos, you can throw the white flag on a hand before you get in too deep on a hand if you aren't confident about it; if the dealer hasn't looked at his cards, you can call an "Early Surrender."

Dealers generally stand on a 17 unless it is a "Soft 17" e.g. Ace-6, Ace-Ace-5, or Ace-2-4. Dealers cannot split their hands in standard rules.

If you sit in the "Third Base" position i.e. the last person who plays) you can see how everyone else is betting, and that will jog your memory to your strategies.

Blackjack Math vs. Luck

There is a certain amount of chance to Blackjack - especially since it can be played with up to 8 decks - but the major plan to employ when playing is Blackjack Math.

Now enter the odds and strategy

The first thing to know is you always want to stand on a hand that adds up to 17 or higher because it is a strong hand and the odds are against you drawing anything that won't cause you to "bust" over 21.

The important stuff. Any hand valued at 11 or lower should automatically be hit as you won't win or bust unless you hit it.

Beware of the dealer showing an ace, lest he gets a 10-valued card next draw. This is more likely than any other value because there are four cards with that value. Remember that the dealer has an advantage because he responds to your play.

Blackjack Probability Table

Since it's the "middle" value cards that offer the most challenge, it is with these that you want to focus your attention. If you have 17 or higher, you're golden, so if you have between 11 and 16, that's the most unstable hand.

Understand that the House has a serious advantage, especially in a multideck shoot. Consider studying the art of counting cards - technically legal even if casinos don't like it - and view it as a way to read the value of each hand. The hi-lo method is what they use in the movie "21" with Kevin Spacey.

Read the book "Beat the Dealer" by Edward Thorp if you are interested in their strategy without the Hollywood flair.

10-valued cards are high, and anything below 6 is a low card. Remember not to play too long in once sitting and set a limit on how much you are open to spending - consider it set in stone and leave when your time is up.

The Math Behind Blackjack ALWAYS Beats Luck

If you don't believe it, check out this lecture by Steven Wu from the Carleton University Math Society.

It's tempting to go over if you're "feeling lucky" but it will just give the casino more of your hard earned money. Not only does playing too long wear down your attention span, but it also makes you draw attention to yourself and the casino will start encouraging you to drink and otherwise distract you, so you stop paying attention.

If you ARE counting cards, Vegas will find a way to discourage you from playing much longer - the ‘Eye in the Sky' camera is always watching.

Remember that, once you learn the basics and understand the mechanics of the game, reading the dealer and developing your style is the way you will have a better shot. Casinos are there to make money, just like you, but they have the advantage. Know this and don't be played by the flashy lights and cheap drinks.

Be calm, don't have too much alcohol, and remember that the ace and ten-cards are the main cards that increase the dealer's odds of beating you. You can have a lot of fun and win money if you pay attention.

Remember that this game will not change whether you have a "warm" or "cool" dealer or if your table is a specific color or position in the casino. If you understand math, particularly if you know statistics, you will have success at the 21 table.

Up Next: Let's Play Some Blackjack!

Now that you know how important mathematics is in a game of blackjack, it's time to move from theory to practice and play some hands. Below, you can see the three best online blackjack sites available this month: check out their offer, choose your favorite bonus, and get ready to hit the blackjack table!

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