The Science of Doubling Down in Blackjack (Essential Tips & Strategy)

Want to double down like a blackjack pro? We reveal the optimal times to double that bet...
Blackjack hand double down
Doubling down is an essential move for any serious blackjack player. It can transform a decent winning opportunity into something incredible. But like most things in this classic card game, it can be a confusing concept for the casual newcomer. Search any gambling forum and you will find many threads starting with "when to double down".

The truth is that there is really no guesswork involved when it comes to doubling down. This isn't a case of following your gut - doubling down is actually a very specific science. There are times when you should absolutely double your bet. And on the flip side, there are times when doubling could lead you to a total wipe out.

But when exactly is the right time to double down? And is there any way for newbies to pick this up quickly? We reveal all in our complete guide to the strange science of the double down play.

What is doubling down in Blackjack?


Before we get into the real meat of this guide - we should start off with a little refresher. A blackjack game starts when you place an ante bet (your buy into the game) - the dealer will then deal you two cards. The option for the double up bet comes when you can choose to either hit or stick.

If you choose to double up, you will place a bet equal to your starting bet. You will then be dealt a third and final card. The game will then continue and you will need to wait to see what the dealer has in his own hand.

In essence, you are betting that the 3rd and final card will give you a hand strong enough to beat the dealer's hand. And this is where the exact science of doubling down comes in. Sure, you could double down on a hard 18 and hope for a three. But you are far more likely to bust.


At the same time, you could end up with an incredibly weak hand. Let's say you are dealt two fives - you double down hoping for that ace. But instead, you end up with a three. Your best hope in this instance is the dealer going bust. 

There's one other factor to consider when doubling down: the dealer's hand. Your hand could show decent potential - but the dealer may have something even better. 


It's important to understand that doubling down can be a rewarding but risky move. Draw that final card - and you are locked into that hand till the bitter end. And this is why doubling down is more of a science than an art.

Using double down in Blackjack


One thing we recommend to all new players is to keep a blackjack strategy chart close by. These are worth their weight in gold - and will help you learn when and where you should double down. But we don't always have convenient access to an electronic device.

For example: if you visit a land-based casino for a bit of fun with your pals. The last thing you want your is your friends to think that you are being anti-social as you furtively check your strategy guide. In this case, it makes sense to memorise a few must double down hands.

Not all casinos have the same rules when it comes to doubling down. For instance, some establishments will let you double down on every single hand combo. But some will only let you double down on hand values 9, 10 or 11. 


Now without further ado, let's take a look at some essential double down moves that produce some of the most reliable results.

Always Double Down on 11

This one is pretty simple to understand. If you are dealt an 11 - then you have a good chance of landing a blackjack victory. This is one of those hands where it doesn't matter what the dealer has: doubling down is simply a must.

The same also goes for hands valued at 10, with some minor exceptions. If the dealer's up card is a 10 or an Ace - then it's recommended to not double down.


Double down on Split Aces

This one is reliant on the rules of your respective gambling venue. But there are some blackjack casinos and games that will allow you to double down after splitting. And in the case of Aces?  You should always double down.

There are more 10 cards than any other card in a single deck. Therefore, there's a good chance that you will land at least one after splitting a pair of aces. That's an instant blackjack win on top of your doubled bet.


Never double down on soft 19 or 20

If you double down on these hands, you are playing a dangerous game. Yes, you could land a blackjack on an A9, but you also risk having a subpar hand.  A more sensible approach is to hit and see if you can land a blackjack - without too much risk of going bust.

What is a soft hand? Basically, it's a blackjack hand that contains an Ace. Aces can either be the value 1 or 11 - making them a flexible and valuable addition to any hand.


Double Down in Blackjack: Summary


Doubling down is one of the most exciting moves in a game of blackjack. And it's one of the most satisfying to witness too. Drawing a 21 hand on a doubled up bet? There's little else out there in the world of blackjack online casinos that compares. If you want to test out your new double up skills, then we recommend playing blackjack at these top casinos.

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