Card counting trainer
Free and without sign-up: count down a deck against the clock, then keep the running count at the blackjack table. Hi-Lo and six other systems.
Deck countdown
Count every card as it comes, then give the running count. Aim for a full deck in under 30 seconds with the right count.
How card counting works
Every card gets a tag. With Hi-Lo, the most used system, the small cards 2 to 6 count +1, the 7, 8 and 9 count 0, and the tens, faces and aces count −1. You add the tags of every card you see, the dealer’s included, and keep the total in your head: the running count.
A positive count means more small cards have gone than big ones, so the shoe is rich in tens and aces, which favor the player: blackjacks pay 3 to 2, doubles hit harder and the dealer busts more. That is when counters bet more. A negative count favors the dealer, and they bet the minimum.
In a shoe the running count is divided by the decks still to be dealt to get the true count, which the bets and a few strategy changes are keyed to. The drill above trains the first skill, speed and accuracy; the table trainer adds the rest.
| Card | Hi-Lo tag |
|---|---|
| 2 | +1 |
| 3 | +1 |
| 4 | +1 |
| 5 | +1 |
| 6 | +1 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 J Q K | −1 |
| A | −1 |
Counting systems compared
Every system is a set of tags. Betting correlation says how well the count predicts the player’s edge; playing efficiency, how well it predicts strategy changes; insurance correlation, how well it calls the insurance bet.
| System | Level | Balanced | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 J Q K | A | Betting | Playing | Insurance |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hi-Lo | 1 | Yes | +1 | +1 | +1 | +1 | +1 | 0 | 0 | 0 | −1 | −1 | 0.97 | 0.51 | 0.76 |
| KO (Knock-Out) | 1 | No | +1 | +1 | +1 | +1 | +1 | +1 | 0 | 0 | −1 | −1 | 0.98 | 0.55 | 0.78 |
| Hi-Opt I | 1 | Yes | 0 | +1 | +1 | +1 | +1 | 0 | 0 | 0 | −1 | 0 | 0.88 | 0.61 | 0.85 |
| Hi-Opt II | 2 | Yes | +1 | +1 | +2 | +2 | +1 | +1 | 0 | 0 | −2 | 0 | 0.91 | 0.67 | 0.91 |
| Omega II | 2 | Yes | +1 | +1 | +2 | +2 | +2 | +1 | 0 | −1 | −2 | 0 | 0.92 | 0.67 | 0.85 |
| Zen Count | 2 | Yes | +1 | +1 | +2 | +2 | +2 | +1 | 0 | 0 | −2 | −1 | 0.96 | 0.63 | 0.85 |
| Wong Halves | 3 | Yes | +0.5 | +1 | +1 | +1.5 | +1 | +0.5 | 0 | −0.5 | −1 | −1 | 0.99 | 0.56 | 0.72 |
Correlations as published by Don Schlesinger (Blackjack Attack) and Stanford Wong (Professional Blackjack). The tags are each system’s own; Wong Halves is usually counted doubled at the table. The drill and the table trainer count with any of them.
True count and index play drills
Two drills for the skills after the countdown: turning the running count into the true count in a shoe, and the handful of plays that change with it.
True count drill
The running count and the decks left: give the true count to the nearest whole number.
Index play drill
A hand, the dealer’s card and the Hi-Lo true count: play it as the Illustrious 18 and the Fab 4 say. Six decks, dealer stands on soft 17.
The Illustrious 18 and the Fab 4, with the engine’s numbers
The Hi-Lo index of each play as published, what basic strategy does instead, what the deviation gains three points past its index, and the count at which the engine finds the two plays crossing for a sample hand with three of six decks left.
| Hand | Dealer | Index | Index play | Basic strategy | Gain at index ±3 | Engine crossover |
|---|---|---|---|---|---|---|
| Insurance | A | +3 | Insurance · +3 or more | No insurance | +0.029 (+6) | +3.5 |
| 16 | 10 | 0 | Stand · 0 or more | Hit | +0.007 (+3) | +2 |
| 15 | 10 | +4 | Stand · +4 or more | Hit | +0.015 (+7) | +5.5 |
| 10,10 | 5 | +5 | Split · +5 or more | Stand | +0.183 (+8) | +5.5 |
| 10,10 | 6 | +4 | Split · +4 or more | Stand | +0.128 (+7) | +5 |
| 10 | 10 | +4 | Double · +4 or more | Hit | +0.020 (+7) | +4 |
| 12 | 3 | +2 | Stand · +2 or more | Hit | +0.027 (+5) | +2.5 |
| 12 | 2 | +3 | Stand · +3 or more | Hit | +0.025 (+6) | +4.5 |
| 11 | A | +1 | Double · +1 or more | Hit | +0.060 (+4) | +1.5 |
| 9 | 2 | +1 | Double · +1 or more | Hit | +0.057 (+4) | 0 |
| 10 | A | +4 | Double · +4 or more | Hit | +0.078 (+7) | +4 |
| 9 | 7 | +3 | Double · +3 or more | Hit | +0.070 (+6) | +2.5 |
| 16 | 9 | +5 | Stand · +5 or more | Hit | +0.013 (+8) | +5 |
| 13 | 2 | −1 | Hit · below −1 | Stand | +0.039 (−4) | −1 |
| 12 | 4 | 0 | Hit · below 0 | Stand | +0.040 (−3) | +1.5 |
| 12 | 5 | −2 | Hit · below −2 | Stand | +0.042 (−5) | −1.5 |
| 12 | 6 | −1 | Hit · below −1 | Stand | +0.029 (−4) | −1.5 |
| 13 | 3 | −2 | Hit · below −2 | Stand | +0.026 (−5) | −2.5 |
| 14 | 10 | +3 | Surrender · +3 or more | Hit | +0.022 (+6) | +4.5 |
| 15 | 10 | 0 | Hit · below 0 | Surrender | +0.040 (−3) | −0.5 |
| 15 | 9 | +2 | Surrender · +2 or more | Hit | +0.034 (+5) | +2.5 |
| 15 | A | +1 | Surrender · +1 or more | Hit | +0.025 (+4) | +1.5 |
Indices from Don Schlesinger’s Blackjack Attack (Hi-Lo, multi-deck). Gains and crossovers are the engine’s exact composition-dependent EVs for a sample two-card hand (16 = 10-6, 15 = 10-5, …) against a six-deck shoe with three decks left, built to stand at that true count; the stand indices for 16 and 15 against a ten assume no surrender, the two ace indices a dealer who stands on soft 17. Other hands making the same total cross at slightly different counts, which is why the published indices are rounded.
Then count at the table
The blackjack trainer deals a real six-deck shoe to a cut card. Turn on the count and it shows the running count, the true count and the decks left under the felt; turn on the quiz and it hides them and asks you for the count every few hands.
Questions about card counting
- How does card counting work in blackjack?
Add 1 for 2–6, subtract 1 for tens and aces, bet more when the count is high.
- What is the true count in blackjack?
Running count ÷ decks left. +6 with 3 decks left = +2.
- Which card counting system is best?
Hi-Lo. Simple, a 0.97 betting correlation, and the system everyone teaches.
- Does card counting work with 6 decks?
Yes, with the true count and a deep cut card. Not against a continuous shuffler.
- How long does it take to learn card counting?
A few weeks to a few months of daily practice, in four steps.
- Is card counting legal?
Yes, if you only use your head. Casinos can still ask you to leave.
- Does card counting work online?
No against software blackjack, which reshuffles every hand. Barely in live dealer games.
Questions and answers
Is this card counting trainer free?
Yes. The drill and the table run in your browser with virtual chips, with no sign-up and no real money. Signing in is optional and only keeps your progress across devices.
Which counting system should I start with?
Hi-Lo. It is simple, balanced, its strategy indices are the ones every book publishes, and its betting correlation of 0.97 is within a hair of the best. Higher-level systems gain very little and cost speed.
How fast should I be able to count down a deck?
The standard target is a full deck in under 30 seconds with the right count every time. Start with one card at a time, then switch to pairs, which is how counters read a table.
Does the count include the dealer’s hole card?
Not until it is turned over. The count strip under the table only counts the cards you can see, and the hole card counts among the cards left, exactly as at a casino table.
Can I practice counting in the game itself?
Yes. In the trainer, open Card counting in the side panel and turn on Show the count. The quiz switch hides the numbers and asks for the running count between hands; your score shows in the session strip.
Where the numbers come from
The tags, the card counts per deck and the true count conversions come from the open-source blackjack engine, which deals the same shuffled shoes the trainer plays. The house edges quoted on the question pages are the engine’s exact figures for each rule set. The correlations of the systems are published values and are labelled as such.