Blackjack – the legendary casino game: online blackjack strategies and rules

You’re probably wondering how to win a lot of money at online blackjack, but don’t know where to start?

That’s why we asked the experts at 21 and created a brilliant guide to learn the blackjack rules and break the bank at any online casino. Here’s the first tip: the casino always has a slight mathematical advantage over the player, so before you sit down to play, check out how not to get ripped off right from the start! 

online blackjack

Pros and Cons of Online Blackjack


  • Simple rules,
  • Very popular game – available in almost every casino,
  • Possibility to influence the outcome of the game with strategies,
  • The only casino game where the player can have an advantage over the casino,
  • With proper bankroll management it is a casino game that allows you to play for a long time.


  • Learning strategies can be difficult at first,
  • No card counting in most online casinos,
  • No possibility to win a large amount (jackpot).

Online Blackjack – rules of the game

Blackjack is a game played against the dealer. At the beginning of online blackjack, the player is dealt two cards face up, and the dealer is dealt one card face up and one card face down. Each card is scored according to the following rules:

Online blackjack – card scoring
Ace 1 or 11 points*
Figure (J-K) 10 points
Cards from 2 to 10 Points according to the value of the card**.
*depending on player choice

**For example, a 9 is 9 points.

Online blackjack – the goal of the game

The goal of the online Blackjack game is to get as many points as possible, but not higher than 21 points. You’re lucky if at the very beginning of the game you get a Blackjack (capitalized), a two card hand – Ace (11 points) and any card from Ten to King (10 points).

Allowed plays in online Blackjack

At the beginning, the player deposits money, the so-called initial bet. After receiving the first two exposed cards, the player can:

Hit – the player asks for another card, usually when he/she is short of points and can later draw another card,

Stand – you keep your cards and decide not to hit any more, now it is the croupier’s turn,

Double down – The player doubles his initial bet and draws another card,

Split cards – if you receive cards of the same denomination (e.g. two fives), you can split them and create two separate boxes. In the second box you place the same bet as the initial one,

Insure – this is an additional bet that can only be played if the dealer’s exposed card is an ace. The player may place an additional bet that the dealer has Blackjack. If this is the case, the player loses the original bet, and the insurance pays out at a ratio of 2 to 1. The insurance rate is half of the original bet, so the player ends up with zero after adding up the losses and winnings.

Online Blackjack – result of the game

After the game is played, the results are compared. If you have more than 21 points, you lose the initial bet and the dealer takes the money.

If you have less than 21 points, the dealer reveals his second card and then follows a simple algorithm: if he has 16 points or less, he draws a card, if he has 17 points or more, he does not draw. The player or dealer with a point total closer to or equal to 21 wins.

Blackjack – counting cards

You can still reduce the advantage of the casino by counting cards, although it must be admitted that in online blackjack the number of decks is often so large that it makes this type of operation impossible.

Card counting in blackjack is almost shrouded in legends, but it is not as difficult as it seems at first glance. It is simple elementary school level math: addition, subtraction and division.

When there are more high cards to be dealt than low cards, the mathematical advantage in the game is temporarily on the side of the player, not the casino.

When a player has an advantage, he should obviously maximize his bets, and in the opposite situation, minimize.

Players who count cards follow the basic strategy with slight modifications depending on the change in the so-called true value, which we will discuss shortly.

Online Blackjack: The Hi-Lo Card Counting Method

The most popular card counting system is the Hi-Lo method, which stands for High and Low. In this strategy, the player assigns an extra value to the cards.

Cards 2-6: have a value of +1
Cards 7-9: 0
T-A: value -1

When you add up the whole deck of cards like this, the sum is 0. This calculation determines the so-called current value. When it is greater than 0, it means that there are more high cards left than low cards. Conversely, when the present value is less than 0, there are more low cards left.

When a card appears you should perform a simple operation in your head. Although it sounds simple, try this strategy first in online blackjack for play money to get used to it.

You get the current value when you perform the basic operations, but what you really need is the so-called true value. To calculate it, you need to divide the current value by the number of remaining decks. For example, if the current value is 8 and there are 4 decks remaining, the true value is 2. The casino’s advantage over the player varies depending on the true value.

Online blackjack – bankroll management 

One of the most popular budget management systems in online blackjack is Kelly Criterion. In this strategy, you place bets that are equal to your casino edge.

For example, if your bankroll is £1000 and your edge is 2%, you bet 2% of your bankroll, or £20.