How to Win at Blackjack
You can't win every hand, and no legal method makes blackjack a sure thing. What you can do is play so the house keeps as little as possible: with perfect basic strategy the house edge is about 0.5%, one of the lowest of any casino game. Most players give away far more than that. In our simulations, copying the dealer's rules gave the house 5.7%, and refusing to ever risk a bust gave it 8.1%.
These 10 tips are ordered by how much they save.
What your playing style costs
We simulated 3 million hands for each style below with House21's rules (6 decks, dealer stands on 17, blackjack pays 3:2). Basic strategy is our 20-million-hand figure.
| How you play | House edge | Lost per 1,000 chips bet |
|---|---|---|
| Perfect basic strategy | 0.5% | 5 |
| Basic strategy, but always take insurance | 0.8% | 8 |
| Hit and stand correctly, but never double or split | 2.4% | 24 |
| Play like the dealer: hit to 17, never double or split | 5.7% | 57 |
| Never risk a bust: stand on 12 or more | 8.1% | 81 |
The last two feel safe and are the most expensive. Each figure is within about ±0.1 points.
1. Learn basic strategy
Everything else on this list is small next to this. Basic strategy is the best move for every hand against every dealer card, worked out by mathematicians in the 1950s. Start with our basic strategy chart; keep it open while you play until you don't need it.
2. Watch the dealer's card, not just yours
The dealer busts about 40% of the time from a 4, 5 or 6 and about 23% from a 10. That's why the same 13 is a stand against a 5 and a hit against a 9. Our bust odds tables show every case.
3. Double down when the chart says so
Doubling is your main way to put more chips out exactly when you're the favorite. Players who never double or split give up about 1.9 points of edge. Always double 11 against anything but an ace, and 10 against 2 to 9. When to double down covers every case with the numbers.
4. Split the right pairs
Always split aces and 8s; never split 10s or 5s. A pair of 8s is 16, the worst hand in the game, and splitting turns it into two hands starting from 8. See when to split pairs.
5. Never take insurance
Insurance is a side bet that loses about 7.6% of what you put on it. Taking it every time adds roughly 0.3 points to the house edge. The full math is short.
6. Don't play scared
Standing on every 12 to 16 so you can never bust is the costliest habit we tested. It hands the house 8.1%, sixteen times the edge of basic strategy. You'll bust sometimes when you hit 12 against a 10. You'll lose more often if you don't.
7. Choose the table rules
The rules matter before the first card. A table that pays 6 to 5 for blackjack instead of 3 to 2 costs you about 1.4% of every bet, more than doubling the edge. Dealer hitting soft 17 adds about 0.2%. Look for 3 to 2, dealer stands on soft 17, and double after split. House21 offers all three.
8. Size your bets to last
Bet size doesn't change your odds; it changes how long you last. Keep each bet near 1% of your chips. With 100 bets behind you, the chance of going broke in 1,000 hands of basic strategy is under 1%. With 20, it's 63%. Our bankroll guide has the full table.
9. Ignore streaks and betting systems
Raising your bet after losses, or after wins, doesn't change the 0.5% on each hand. It only changes when the swings happen. A losing streak tells you nothing about the next hand; is online blackjack rigged? explains why long streaks are normal.
10. Know when to stop
A stop point doesn't improve your odds, but it does lock in a good session and end a bad one before it gets worse. Decide before you sit down: a number of hands, a time, or a win and loss limit.
How often will you actually win?
Per hand, a basic strategy player wins 43%, loses 48% and pushes 9%. You still come out almost even, because blackjacks pay 3 to 2 and doubled hands win twice the bet.
Over a session, luck dominates. Over thousands of hands, the edge shows:
| Hands played | Chance to be ahead (basic strategy) |
|---|---|
| 100 | 48% |
| 1,000 | 44% |
| 10,000 | 33% |
So on any given night, you're close to a coin flip to finish up. That's the best realistic definition of winning at blackjack: give the house as little as possible and enjoy the nights you're ahead.
What about card counting?
Counting cards can tip the edge to the player, but only in games dealt deep into a shoe, and the gain is small: in our simulations, a Hi-Lo counter betting 1 to 8 units reached about +0.4%. Most online blackjack reshuffles every hand, so there's nothing to count. Does card counting work online? goes through it.
How we calculated this
Each style was played for 3 million hands from a 6-deck shoe reshuffled when 52 cards remain, with the dealer standing on all 17s and checking for blackjack. "Play like the dealer" hits any total under 17; "never risk a bust" hits only 11 or less. The insurance figure combines insurance's -7.6% return with how often the dealer shows an ace (1 hand in 13).
Put the tips into practice at a free table in the House21 lobby. Chips are virtual, so learning costs nothing.