Two of the most-well known and popular features of blackjack are splitting and doubling down on particular hands. The first, of course, refers to when you receive a pair of cards of the same value immediately after the cards are dealt and you “split” them by turning them into two hands with your initial bet also being placed on the new second hand. Doubling down occurs after you are dealt your first two cards and you believe that one last card will guarantee you a win and you immediately double your initial bet.

Both are brilliant tools to win a lot on a single hand with doubling down obviously doubling your winnings, potentially, and splitting doubling up your bet but also doubling up your chances. They should not, however, be used with abandon as they can backfire and you can lose twice the amount of money you initially wagered.

Blackjack, though, is a game built on probabilities so there are specific hands that have a higher chance to pay off than others. 

Here is a guide to both.

Doubling Down

Like we established above, doubling down occurs only after you are dealt your first two cards, but there are only specific cards – both in your hand and the dealer’s – that you should risk doubling down on. There are, in fact, three specific situations that you should really go for broke and double down on. 

• You have a hard nine (and two cards that don’t include an ace that add up to 9) AND the revealed card of the dealer falls between two and six, inclusive. 
• You have a hard 10 or 11 (again, no aces) and the dealer’s card is any number lower than that. 
• You have a soft 16, 17 and 18 (“soft” meaning that one of the cards can be an ace) and the dealer has a card between 2 and 6, inclusive.  

These work by ensuring that you can never go bust with that third card and that the odds are in your favor to beat the dealer. Doubling down on any other hand is very risky.

Splitting

Like doubling down, splitting is a last-ditch effort to immediately double your money on the play of a single card and like doubling down, you should only really do it for certain cards, both in your hand and in the dealer’s. The way they break down, though, is slightly different. 

There are two pairs on which you should always split. These are:

• Pair of Aces. Because of the many different cards in the game worth 10 (10s and all picture cards), splitting on aces doubles your chance of getting a blackjack. 
• Pair of 8s. Having cards that equal 16 is never ideal as there is a very high chance that the dealer will end up with 16 or higher in their own hand and you can bet no further. Split the 8s and because of the prevalence of value 10 cards, you’re more likely to get an 18, which is a much surer hand.

Other than these two hands that are a must-split, there are three other hands that it pays to split, but with each one dependent on both your cards and the revealed card of the dealer. Here’s how they break down: 

You don’t have to split on these, but the chances of winning on these splits are in your favor. As you may have noticed, value 10 cards are not good to split on, despite being known for exactly that. On 10 value cards, you may draw an 8, 9, 10 or ace, but you can just as easily draw from 2 to 6 and any of those will leave you in a real pickle against most of the dealer’s hands.  

Just remember, both splits and doubling down are incredibly powerful tools in blackjack – just make sure you know how to use them to your advantage.