Guide hub
Blackjack: Rules, Odds and Strategy Guides Backed by 40 Million Simulated Hands
Blackjack can have a house edge under 0.5%, but only if you play the right table the right way. Our guides show exactly how much the rules and your decisions cost, using our own simulation data.
| House edge, 6 decks S17 DAS, 3:2 | about 0.47% in our simulation |
|---|---|
| Same game paying 6:5 | about 1.83% in our simulation |
| Paid blackjacks | about 1 hand in 22 |
| Dealer hits soft 17 (H17) | adds about 0.18 percentage points in our simulation |
| Best tool | Blackjack calculator: the right move for any hand |
All guides in this section
- GuideLive Blackjack Explained: How It Works, the Real Odds and the Rules to CheckLive blackjack explained: how dealer-streamed tables work, how they differ from RNG blackjack online, and each rule set's house edge from our 10M-hand sim.
- Guide6 to 5 Blackjack vs 3 to 2: What 10 Million Hands Show About the Real Cost6 to 5 blackjack roughly quadruples the house edge. We scored the same 10 million hands at 3:2 and 6:5 to show the real cost in USDT, rule set by rule set.
- GuideBlackjack Strategy Chart: Every Hand for 6-Deck Games, With H17 ChangesFree blackjack strategy chart for 6-deck games: hard, soft and pair tables for every dealer upcard, the H17 changes, and the edge our 10M-hand test measured.
- ToolBlackjack Calculator: The Best Move for Any Hand and Rule SetFree blackjack strategy calculator: enter your cards, the dealer's upcard and table rules to get the basic-strategy move and house edge from 10M hands.
- GuideWhat Does Split Mean in Blackjack? Split Rules, Aces and When to Do ItWhat does split mean in blackjack? How splitting works, when to split each pair, why two aces don't win alone, and what our sim says DAS is worth.
- GuideCard Counting Resources: How to Count Cards in Blackjack, Honestly ExplainedCard counting resources: how the Hi-Lo count works in blackjack, why it fails in games shuffled every hand, where it's legal, and the edge it must beat.
- GuideDouble Deck Blackjack Strategy: Which Rules Matter and What Two Decks Are WorthDouble deck blackjack strategy: what two decks are worth (+0.19% vs 8 decks), which rules cost more than that, and where to find the right 2-deck chart.
- GuideOnline Blackjack for Real Money: How It Works, What It Costs and Which Tables to ChooseHow online blackjack for real money works: RNG vs live tables, the house edge of each rule set from our 10M-hand sim, legality checks and USDT bankrolls.
- GuideWhat Is a Push in Blackjack? The Tie Rule Explained With ExamplesWhat is a push in blackjack? A tie where your bet comes back. See worked examples, the blackjack-vs-blackjack case, and how pushes enter house edge math.
- GuideBlackjack Trainer: Practise Basic Strategy Hand by HandFree blackjack trainer: practise basic strategy for 6-deck S17 games, learn the hands players miss most, and see what perfect play is worth in our sim.
- GuideBlackjack App Guide: What to Check in Free and Real-Money Blackjack AppsWhat to check in a blackjack app: rules and payouts, RNG testing, licensing and offline practice, with each rule set's house edge from our 10M-hand sim.
- GuideBlackjack Machine Explained: How Electronic Blackjack Works and Which Paytables to AvoidHow a blackjack machine works: RNG vs shuffler, why 6:5 and even-money blackjack paytables matter, and the edge each one adds based on our 10M-hand sim.
- GuideBeating Online Blackjack: An Honest Look at Strategy, Counting and the House EdgeIs beating online blackjack possible? Why basic strategy only minimises the edge, why counting fails when decks reshuffle, and what our 10M-hand sim shows.
- GuideCard Counting Practice: Step-by-Step Hi-Lo Drills, From First Deck to True CountCard counting practice drills for Hi-Lo: deck countdowns, true count answers, what a counting simulator should do, and why RNG games make counting moot.
- GuideHow to Deal in Blackjack: The Dealing Order, Dealer Rules and PayoutsHow to deal in blackjack for a home game: dealing order, checking for blackjack, S17 vs H17 dealer rules, paying 3:2, and what each rule costs players.
- GuideMartingale System in Blackjack: How It Works and Why Doubles, Splits and Pushes Break ItMartingale system blackjack explained: why doubles, splits, pushes and 3:2 payouts wreck the doubling plan, plus our 50,000-session Martingale test.
- GuideBlackjack Hand Signals: How to Hit, Stand, Double and Split Without Saying a WordBlackjack hand signals for face-up and face-down games: tap or scrape to hit, wave or tuck to stand, and how to double or split, plus the etiquette rules.
- GuideBlackjack Strategy Book Reading List: The Papers and Books That Built Basic StrategyA blackjack strategy book reading list: Baldwin et al. (1956), Thorp (1962), Wong (1975) and Griffin (1979), what each did and how it applies today.
- ToolFree Blackjack Game: Play 6-Deck Blackjack With Live Strategy HintsPlay free blackjack online with no download or sign-up. A 6-deck game that pays 3:2, with optional basic strategy hints and a tally of how often you follow them.
- GuideBlackjack Strategy: What Actually Lowers the House Edge, Tested on 10M HandsBlackjack strategy that works: the basic strategy rules worth memorising, how much table rules matter, why betting systems fail, and our 10-million-hand test.
- GuideBlackjack Rules: How to Play Blackjack, From Card Values to SplittingBlackjack rules explained simply: card values, how a round works, hit, stand, double, split, the dealer's rules, payouts, and which rule variations cost you most.
Blackjack is a card game you play against the dealer, not against other players. You and the dealer both start with two cards, and the goal is to finish closer to 21 than the dealer without going over. Number cards count at face value, jacks, queens and kings count 10, and an ace counts 1 or 11, whichever helps you more. An ace plus a 10-value card as your first two cards is a "blackjack", which traditionally pays 3 to 2.
What makes blackjack different from roulette or slots is that your choices matter. Every time you hit, stand, double or split, you move the house edge up or down. The rules of the table matter just as much, and some of them are easy to miss. That holds on electronic tables too: our guide to blackjack machines shows which paytables to avoid.
Blackjack odds by rule set
We simulated 10 million hands for each of four common 6-deck rule sets, 40 million hands in total, with a computer playing perfect basic strategy. Each hand was scored twice: once with blackjack paying 3:2 and once paying 6:5.
| Rule set | House edge, 3:2 | House edge, 6:5 | Standard error (pp) |
|---|---|---|---|
| 6 decks, S17, DAS | 0.47% | 1.83% | ±0.036 |
| 6 decks, S17, no DAS | 0.53% | 1.89% | ±0.036 |
| 6 decks, H17, DAS | 0.65% | 2.01% | ±0.036 |
| 6 decks, H17, no DAS | 0.78% | 2.13% | ±0.036 |
How to read it: S17 means the dealer stands on soft 17, H17 means the dealer hits it. DAS means you may double down after splitting a pair. A house edge of 0.47% means you lose about 0.47 USDT for every 100 USDT you bet, on average, over a very large number of hands.
Three takeaways:
- The payout is the biggest rule. Switching from 3:2 to 6:5 adds about 1.36 percentage points (1.827 − 0.470). No other rule in the table comes close.
- H17 and no DAS add up. The worst 3:2 game in our table (0.78%) costs you roughly 1.7 times as much as the best one.
- These are Monte Carlo estimates. Each figure has a standard error of about 0.036 percentage points. The rule-change costs published by the Wizard of Odds agree closely with the gaps in our table, all within 0.08 percentage points; the 6 to 5 blackjack guide shows the comparison.
How to use our blackjack guides
Start with the basics, then move to the numbers that save you the most money:
- 6 to 5 vs 3 to 2 blackjack: our centrepiece comparison. The same 10 million hands scored under both payouts, plus how to play blackjack from scratch.
- Blackjack strategy card: the full basic strategy chart for a 6-deck S17 game, colour-coded, with the changes you need when the dealer hits soft 17.
- What splitting means in blackjack: when to split, when not to, what happens with two aces, and what doubling after a split is worth.
- Live blackjack explained: how dealer-streamed tables work, how they differ from digital blackjack, and which rules to check before you sit down.
- Card counting resources: an honest explanation of the Hi-Lo count, why it fails in games that shuffle every hand, and where counting is legal.
Featured tool: the blackjack calculator
Charts are useful, but sometimes you just want the answer for one hand. Our calculator gives you the basic strategy move for any hand against any dealer upcard, for the rule set you're playing.
The charts behind the calculator and our strategy card follow the Wizard of Odds basic strategy for 4 to 8 decks. Our simulation then measured what that strategy actually returns under each rule set.
Blackjack with crypto and USDT
Blackjack's low edge makes each hand cheap to play, which also means small costs elsewhere stand out. Two points for crypto players:
- Fees can outweigh the edge. At 0.47%, betting 1,000 USDT in total costs about 4.70 USDT on average (1,000 × 0.47%). A single network fee on deposit or withdrawal can be a meaningful share of that. Our USDT and payments guides explain how network choice affects fees.
- A stablecoin keeps the maths clean. If your bankroll is in BTC or ETH, the coin's price can move more in an evening than the house edge does. Holding USDT means the only swings are the game's.
If you also play crypto-native games, compare blackjack's edge with the 1% built into the published crash formula in our crash gambling breakdown. A well-ruled blackjack table played with basic strategy has the lower edge; a 6:5 table does not.
Frequently asked questions
What is the house edge in blackjack?
It depends on the rules. In our 10-million-hand simulation of a 6-deck game where the dealer stands on soft 17, doubling after splits is allowed and blackjack pays 3:2, the house edge was about 0.47% with perfect basic strategy. Paying 6:5 instead pushed it to about 1.83%. Playing by feel costs more than either figure.
Can you beat blackjack?
Not with basic strategy alone. Basic strategy only minimises the house edge; it does not remove it. Card counting can shift the odds in a dealt shoe game, but it does nothing in online games that shuffle every hand, and Nevada casinos, for example, may bar counters. Treat blackjack as entertainment with a small, known cost.
Is 3:2 or 6:5 blackjack better?
3:2 is always better for you. On the same 10 million simulated hands, a 6:5 payout raised the house edge from about 0.47% to about 1.83%, close to four times as much. Check the payout printed on the table or in the game rules before you place a bet.
How many decks are used in blackjack?
Games use anywhere from a single deck up to eight. Fewer decks slightly favour the player: the Wizard of Odds rule tables credit a single-deck game with about 0.48 percentage points less house edge than an eight-deck game, other rules being equal. Our simulation uses six decks, a common shoe size.
Sources
- Blackjack Rule Variations — Wizard of Odds
- Blackjack Basics — Wizard of Odds
- 4-Deck to 8-Deck Blackjack Strategy — Wizard of Odds
- Blackjack: How to Play — Bicycle Cards
- Legal or Not, Card Counting Is Not Appreciated at Las Vegas Casinos — Nevada Public Radio (KNPR)