Online blackjack

How online blackjack works

Blackjack, or 21 as the card game is also known, is played against the dealer and not against the other players. The aim is to get a hand closer to 21 than the dealer’s, without going over. If you go over 21 you are “bust” and lose your stake immediately, regardless of what the dealer then gets.

The cards have the following values:

• 2–10 count at face value.
• Jack, queen and king count as 10.
• An ace counts as 1 or 11, depending on what is best for the hand.

A hand with an ace counted as 11 is called soft, for example ace and six, which makes soft 17. An ace and a ten-value card straight from the deal is a natural blackjack, the best hand in the game.

Each round begins with you placing your stake. You and the dealer get two cards each, and the dealer shows one of theirs. Then you choose how to play the hand:

• Stand – you are happy with the hand.
• Hit – you draw another card, and can carry on as long as you do not go over 21.
• Double – you double your stake and get exactly one more card.
• Split – if you have two cards of the same value, you can split them into two hands, each with its own stake.
• Surrender – at tables that allow it, you can give up the hand and get half your stake back.

When all players are done, the dealer turns over the hidden card and draws according to fixed rules. The dealer must stand on 17 or more, but at some tables the dealer also hits soft 17, which is worse for you.

Online, blackjack is available both as an RNG game, where a random number generator shuffles the cards and you play at your own pace, and at tables with a real dealer in a studio. The rules and the maths work the same way in both formats.

If the casino offers RNG blackjack in demo mode, you can play for free. It is a good way to practise basic strategy without pressure and without it costing anything, before you sit down at a table with real stakes. Just bear in mind that results in demo mode tell you nothing about how things will go when you play for real.

Blackjack payouts

The payouts in blackjack are few and easy to remember. The table shows the standard payouts and what they mean for a stake of 100 kr.

The row to look at especially carefully is the one for natural blackjack. A table that pays 6:5 gives you 30 kr less per blackjack on a 100 kr stake. According to Wizard of Odds, 6:5 instead of 3:2 costs the player about 1.39%, which is more than the entire house edge at a good table. So always choose tables that pay 3:2.

Rule variants that affect the house edge

Blackjack is really a whole family of games with slightly different rules, and each rule shifts the house edge a little one way or the other. That is why two tables that look identical can have quite different expected costs.

The figures come from Wizard of Odds and assume that you follow basic strategy. If you play by feel, the house edge becomes considerably higher. The rules for a particular table are in the game’s information panel, and it is worth a minute to read them before you sit down.

Blackjack strategy and probability

Basic strategy is a chart that gives the mathematically best decision for every combination of your hand and the dealer’s upcard. It is derived by simulating or calculating all possible outcomes, and it lowers the house edge to the levels in the table above. It does not, however, make the game profitable: the house still has an edge in the long run.

How often do you get blackjack?

There are 16 ten-value cards and 4 aces in a 52-card deck. The chance of being dealt a natural blackjack is therefore 2 × (4/52) × (16/51) ≈ 4.8% with one deck, roughly once in 21 hands. With more decks the figure is almost the same. That is also why 3:2 or 6:5 matters so much – blackjacks come often enough for the payout to be noticeable in the long run.

Why insurance is rarely worth it

If the dealer shows an ace, you are offered insurance, a side bet of half your stake that pays 2:1 if the dealer has blackjack. Do the maths with one deck and ignore your own cards: 16 of the 51 remaining cards are ten-value. The insurance therefore wins 16 times in 51 and loses 35 times. With 1 kr in insurance, the expected value is (16 × 2 − 35) / 51 ≈ −5.9%. With six decks it is even worse, about −7.4%. In other words, insurance is a separate bet with considerably worse odds than the blackjack game itself.

Worked example: what does an evening at the table cost?

Say you play 100 hands at 100 kr each, so you wager 10,000 kr. The expected cost is then roughly:

• 28 kr with generous rules and basic strategy (0.28%)
• 43 kr with Atlantic City rules and basic strategy (0.43%)
• Around 139 kr more if the table also pays 6:5 for blackjack

By comparison, the expected cost in European roulette is 270 kr for the same amount wagered. More about the odds there can be found in our guide to online roulette. Note that reality swings sharply around these figures in any single session.

Betting systems do not change the odds

The Martingale and other progression systems, where you raise your stake after a loss, do not change the house edge in blackjack either. They only increase the risk of a big loss during a bad run. The only things that affect your expected loss are the rules, your strategy and how much you wager.

How to use basic strategy in practice

Basic strategy looks complicated the first time, but it follows a clear logic. The stronger the card the dealer shows, the more reason you have to hit on medium-strength hands. If the dealer shows a weak card, there is a greater chance the dealer will go bust, and then it can pay to stand earlier or double.

Keep a strategy chart handy when you play RNG blackjack, where you set the pace yourself. At a table with a dealer, the time for each decision is limited, so it is good to have practised the most common situations first. Do not deviate from the chart because you “have a feeling” – it is exactly those deviations that raise the house edge.

Common blackjack mistakes

Many players lose more than necessary because of a few recurring mistakes:

• Playing at 6:5 tables. The payout looks almost the same, but it costs more than the entire house edge at a good table.
• Taking insurance. As calculated above, insurance has a clearly negative expected value, even when you have a good hand.
• Copying the dealer. Always standing on 17 and always hitting below 17 sounds logical, but it ignores the dealer’s upcard and is worse than basic strategy.
• Chasing losses with bigger stakes. It does not change the odds, only how much is at stake.
• Playing side bets out of habit. They have their own maths, which is not affected by basic strategy – read what they cost before you place them.

Online blackjack variants

Besides classic blackjack, there are several variants with their own rules and side bets. Side bets have their own house edge, so always read the information panel.

• Infinite Blackjack (Evolution) – according to Wizard of Odds, the house edge is 0.45% with optimal strategy.
• ONE Blackjack, Free Bet Blackjack and Blackjack X (Pragmatic Play Live) – variants with their own rule additions that affect the odds in different ways.
• Exclusive tables – LeoVegas, for example, has its own blackjack table from OnAir Entertainment.

If you want to play against a real dealer rather than a random number generator, the tables are gathered on our page about live casino.

Blackjack and bonus terms

Swedish casinos may only give a bonus on the first occasion you play, and the terms often steer players away from table games. At LeoVegas, for example, table games contribute 10% to the wagering requirement, Mini Blackjack 10% and Evolution’s tables 0%. Slots, on the other hand, contribute 100%, with the exception of certain titles.

This means that 1,000 kr played on blackjack only counts as 100 kr towards the wagering requirement, or not at all if you play with a live dealer. If you mainly plan to play blackjack, it may therefore be better to skip the bonus. At Mr Green, according to the promotion page, the deposit bonus applies to both casino and live casino, but how much blackjack contributes is not stated – check the terms before you deposit money. The offers were checked on 15 October 2026. Terms and conditions apply.

You will find the games that most often count in full towards wagering requirements in our guide to online slots. Remember that you can always decline a bonus and play without conditions.

Best blackjack casinos with a Swedish licence

The casinos below are licensed by Spelinspektionen (the Swedish Gambling Authority) and name their own live providers. We have not played at the tables; the comparison is based on the casinos’ own information and terms.

LeoVegas has, in addition to Evolution’s range, an exclusive blackjack table from OnAir Entertainment. The casino states over 3,000 games in total.

Unibet has Evolution for live casino and an app for iOS and Android. While wagering a bonus, the maximum stake is 25 kr per game according to the terms.

Casumo and ComeOn both have Evolution’s live casino. Casumo also offers many responsible gambling tools, including loss and session time limits. More options can be found in our list of licensed Swedish casinos.

Play blackjack responsibly

Blackjack having a low house edge does not mean you cannot lose a lot. The expected cost grows with every krona you wager, and high stakes produce big swings. Decide on a budget and a time limit before you start. All Swedish casinos require a deposit limit per day, week and month, and an increase takes effect after 72 hours at the earliest.

If you want to take a break, you can exclude yourself for 24 hours at the casino or at all licensed operators via Spelpaus.se, the national self-exclusion register. Stödlinjen, the national gambling helpline, answers on 020-819 100 and has a chat at stodlinjen.se. You will find more casino games and guides in our overview of online casino games.