Basic strategy, 4–8 decks
Basic strategy is the single best play for every hand you can be dealt, ignoring what has already come out of the shoe. Played perfectly it cuts the house edge to roughly 0.5% in a good 3:2 game. Everything else on this site assumes you have this memorized cold — not "mostly", cold.
The chart in words — the memory hooks
- Dealer's bust cards are 2–6. Against them you stand on stiff hands (12–16) and get aggressive with doubles and splits. Against 7–Ace you assume the dealer has 17+ behind and play to reach 17 yourself.
- Hard 12 vs 2 or 3 is a hit. It feels wrong; it's the most commonly botched cell. Dealer 2 and 3 bust less often than people think (35% and 37%).
- Always split Aces and 8s. Never split 10s or 5s. Two 8s is a 16, the worst hand in the game; two separate 8s is two mediocre hands. Two 5s is a 10 — double it.
- Soft 18 (A,7) is not a good hand. Double it against 3–6, stand against 2, 7, 8, hit against 9, 10, Ace.
- Surrender 16 vs 9, 10, Ace and 15 vs 10. Giving up half a bet beats losing about 77% of the time.
- Never take insurance or even money unless you're counting and the true count is +3 or higher. It's a side bet on the dealer's hole card at bad odds.
- 9s split against 2–6 and 8–9, but stand against 7 (dealer's likely 17 loses to your 18).
Hi-Lo card counting
Basic strategy gets you to "loses slowly". Counting is what gets you to a positive expectation. The idea: high cards (10s and Aces) help the player — more blackjacks paid 3:2, more dealer busts, better doubles. Low cards help the dealer. When the remaining shoe is rich in high cards, you bet more and tweak a few plays.
Card values
| Cards | Add |
|---|---|
| 2, 3, 4, 5, 6 | +1 |
| 7, 8, 9 | 0 |
| 10, J, Q, K, A | −1 |
A full deck sums to zero, which is why the classic practice drill is counting down a whole deck and landing on 0.
Running count → true count
True count = running count ÷ decks remaining. In a 6-deck shoe with two decks in the discard tray and a running count of +8, the true count is 8 ÷ 4 = +2. Estimate decks remaining from the discard tray to the nearest half deck. Round the true count down toward zero (be conservative).
Bet ramp (6 decks, 1–12 spread)
| True count | Bet | Your edge (approx.) |
|---|---|---|
| +1 or less | 1 unit | −0.5% to 0% |
| +2 | 2 units | +0.5% |
| +3 | 4 units | +1.0% |
| +4 | 8 units | +1.5% |
| +5 and up | 12 units | +2.0% or more |
Each point of true count is worth roughly 0.5% to you. Your edge is only positive from about +2 up, so 1 unit at anything lower is the price of staying at the table. Where possible, leave the table ("wong out") when the true count drops below −1.
Reading the sizing
Unit = your bankroll ÷ 1000 for a comfortable risk of ruin (about 5%), or ÷ 500 if you accept a rougher ride. A $10,000 bankroll means $10 units and a $10–$120 spread.
Drill: running count
Pro habit: count in pairs. A 5 and a King cancel — say nothing. Two lows are "+2" as one thought. This roughly halves the work and is how counters keep up with a fast dealer.
Drill: true count and bet
Index plays: the Illustrious 18 and the Fab 4
Once the count is high or low enough, a handful of basic-strategy plays flip. These 22 plays capture about 80–90% of the value available from all possible deviations, so no serious counter learns more than these to start. Rule for every row: take the index play when the true count is at or above the index; otherwise play basic strategy. For negative indices that means you hit (deviate from basic) only when the count is below the number.
| Hand | Index | Play at or above index | Otherwise | Why |
|---|
Insurance at +3 is the single most valuable deviation on the list — worth more than all the others put together in many games. Learn it first, then 16 vs 10, then 15 vs 10.
Drill: index plays
Playbook: everything around the cards
Most people who lose at blackjack don't lose because of strategy. They lose because they sit down at the wrong table, bet too much of their bankroll, and take side bets. Game selection and money management are where the real edge lives.
1. Choose the table before you choose your seat
| Rule | Effect on your edge | Verdict |
|---|---|---|
| Blackjack pays 6:5 instead of 3:2 | −1.4% | Walk away. No counting can fix this. |
| Dealer hits soft 17 (H17) | −0.2% | Prefer S17 tables. |
| Fewer decks (single or double vs 6–8) | +0.3% to +0.5% | Fewer is better, if the other rules are decent. |
| Double after split allowed (DAS) | +0.14% | Want it. |
| Late surrender | +0.08% | Want it. Rare in North America, common in Asia and Europe. |
| Re-split aces allowed | +0.07% | Nice to have. |
| Double only on 10–11 | −0.18% | Avoid. |
| Continuous shuffling machine (CSM) | counting impossible | Fine for basic strategy, useless for counting. |
| Deep penetration (dealer cuts off less than 1 deck of 6) | big for counters | The most important factor for a counter's profit. |
A "good" shoe game: 6 decks, 3:2, S17, DAS, surrender, 1 deck or less cut off. Perfect basic strategy there faces about −0.3%. A 6:5 game with H17 and no DAS is closer to −2%, four to five times worse.
2. Bankroll and risk of ruin
- Your bankroll is money that is only for blackjack and that you can lose entirely without it changing your life. It is not your rent, your savings, or a credit card.
- Basic strategy player: bring at least 40 minimum bets to a session and expect 30–40% of sessions to be losers even playing perfectly. Standard deviation on a hand is about 1.15 bets; over 100 hands that's ±11.5 bets of pure noise on top of the tiny expected loss.
- Counter: total bankroll of 500–1000 units for a 1–12 spread. Less than that and a normal losing streak can wipe you out even with a positive edge.
- Set a loss limit before you sit down. Not because "the table is cold" — that's superstition — but because tilt is real and tired players misplay hands.
Bet sizing calculator
3. Things that are always a mistake
- Side bets (Perfect Pairs, 21+3, Lucky Ladies, Bust It): house edges of 3–13%. They exist because they're where the casino makes its money back from decent players.
- Insurance and even money without a count. The bet pays 2:1 but the dealer has a 10 underneath only 4/13 of the time (30.8%), not 33.3%. You'd take insurance only when the true count is +3 or more.
- Betting systems (Martingale, Paroli, 1-3-2-6, D'Alembert). None change the house edge; they only change the shape of the variance. Martingale in particular turns many small wins into rare catastrophic losses at the table max.
- Playing "hunches" or following the table. Other players' decisions do not change your long-run results in any direction. Third base "taking the dealer's bust card" is a myth: it helps and hurts equally.
- Standing on 16 vs 10 "because you'll bust". You'll bust 62% of the time hitting and lose 77% of the time standing. Hitting is still less bad. Surrender if you can.
- Never doubling soft hands. Soft doubles are among the most profitable plays; players who skip them give back ~0.1% for nothing.
4. Table conduct that makes you look like a regular (and keeps you welcome)
- Use hand signals in shoe games: tap for hit, wave flat for stand, place a matching bet beside (not on top of) your original to double or split. Cards are never touched in a face-up game.
- Never hand money to the dealer; lay it on the felt. Colour up (exchange small chips for large) before you leave.
- Tip occasionally by placing a small bet for the dealer in front of yours. Good for the atmosphere, and a dealer who likes you deals a deeper penetration more often than one who doesn't.
- If you count: raise bets gradually, don't jump from 1 to 12 in one hand, bet big after a win when you can, take a break when the count is terrible instead of visibly sitting out, and keep sessions under an hour at one property. Casinos can and do ask counters to leave; it's legal for them and legal for you. Never use a device — that's a crime in most jurisdictions.
- Look like you're having fun. Serious silent players staring at the discard tray get noticed.
5. The honest numbers
| Player | Edge | Expected result per $10,000 wagered |
|---|---|---|
| Typical tourist ("gut" play, some side bets) | −2% to −4% | −$200 to −$400 |
| Perfect basic strategy, good rules | −0.3% to −0.5% | −$30 to −$50 |
| Perfect basic strategy plus 22 index plays, flat betting | about −0.2% | −$20 |
| Hi-Lo counter, 1–12 spread, good penetration | +0.5% to +1.5% | +$50 to +$150 |
Being in the top 1% of blackjack players is not about winning big nights. It is about having a positive expectation and a bankroll large enough to survive the variance until it shows up. That takes the chart at 100%, a count you can hold through a conversation, and the discipline to leave bad games. This site trains the first two; only you can supply the third.
A four-week training plan
| Week | Goal | Daily work (20–30 min) |
|---|---|---|
| 1 | Basic strategy to 100% | Strategy drill, all hands. Read the reasoning for every miss. Finish when you hit 200 in a row with no errors. |
| 2 | Speed and pair counting | Strategy drill under 3 s per hand. Count down a full deck at "casino" speed, landing on 0 ten times in a row. Then count a real deck of cards in under 30 seconds. |
| 3 | True count and betting | Two-deck countdowns at "fast". True count drill until conversion is instant. Bet sizing from memory. Watch a real table (or play free online) and keep the count while a friend talks to you. |
| 4 | Deviations | Insurance, 16 v 10, 15 v 10 first; then the rest of the I18 and Fab 4. Deviation drill to 100%. Play a low-stakes live session and audit yourself afterwards. |
Self-test before you play for real money
- Strategy drill: 500 hands, zero mistakes, average under 3 seconds.
- Count a physical deck in under 25 seconds, correct 10 times in a row.
- Recite the bet ramp and all 22 indices from memory.
- Know the exact rules, deck count, and penetration of the table you intend to play, and its house edge.
- Have a written bankroll figure and a written session loss limit.
Books and sources this material is drawn from
- Edward Thorp, Beat the Dealer — the origin of card counting.
- Stanford Wong, Professional Blackjack — Hi-Lo and index play in full.
- Don Schlesinger, Blackjack Attack — the Illustrious 18, bankroll and risk math.
- Arnold Snyder, Blackbelt in Blackjack — practical play and camouflage.
- The Wizard of Odds site — house-edge calculators for any rule set.