Edge 21How to count cards in blackjack
Counting cards isn't memorizing the deck or having a genius mind: it's keeping one single number in your head that goes up and down with the cards that come out. That number tells you when more high cards are left in the shoe, which is when the player has the edge. Here's the world's most used method, Hi-Lo, in 4 steps.
Why it works
High cards (10, J, Q, K and Ace) favor you: there are more blackjacks (which pay 3 to 2), your doubles do better and the dealer, who must hit until 17, busts more often. Low cards (2 to 6) favor the dealer. When lots of low cards are already out, more high cards are left in the shoe, and that's when betting more pays off.
Step 1 · Each card's value
Add or subtract like this for every card you see. That's it.
Step 2 · The running count
You start at 0 after the shuffle and add the value of every card that appears on the table: yours, the other players' and the dealer's. That total is the running count. For example: a 5 comes out (+1), a K (−1), a 3 (+1) and a 6 (+1): the running count is +2.
Try it: count these cards
10 cards will come out, one by one. Keep the Hi-Lo count and type the running count at the end.
Step 3 · The true count
A +6 doesn't mean the same with 6 decks left as with 1. So you divide the running count by the decks left to be dealt (estimated by looking at the discard tray). The result is the true count, and that's the one that matters.
| Running count | Decks left | True count |
|---|---|---|
| +6 | 6 | +1 |
| +6 | 3 | +2 |
| +6 | 1.5 | +4 |
| −4 | 2 | −2 |
Step 4 · How much to bet
With a true count of +1 or less, bet the minimum (1 unit). From +2, raise it gradually. A careful example:
| True count | Bet |
|---|---|
| +1 or less | 1 unit |
| +2 | 2 units |
| +3 | 4 units |
| +4 or more | 6 to 8 units |
The edge from counting is small (1 to 2%) and shows up in the long run, over hundreds of hours. In the short run you can lose, even counting perfectly.
4 myths about counting cards
- “It's illegal.” Counting in your head is legal in most places. What's prohibited is using devices at the table, and the casino can ask you not to play blackjack.
- “You have to memorize every card.” You keep a single number.
- “You have to be a genius.” It's adding and subtracting one at a time. The hard part is doing it fast at a full table: that's trainable.
- “Counting means you always win.” The edge is small and long-term. That's why it's for learning and understanding the game, not for getting rich.
What's next: counting for real
Understanding Hi-Lo takes ten minutes. Counting a whole shoe, fast and without it showing, takes practice.
The counting path
10 levels, from each card's value to counting a whole shoe at casino speed, with Hi-Lo or KO.
The daily challenge
A different format every day and a leaderboard to compare yourself with others.
Deviations
Using the count to play too: the Illustrious 18 and the Fab 4, which add most of the extra edge.
Advanced systems and real casino
Hi-Opt I and II, Zen, Omega II and Wong Halves, casino mode with your money and surveillance, and the bankroll simulator to know how much you need.
Frequently asked questions
Is counting cards legal?
Counting in your head is legal in most places. Using a phone or any device at the table is prohibited, and the casino can ask you to stop playing.
How long does it take to learn to count?
The values take minutes. Keeping the count of a whole shoe, fast and at a full table, takes weeks of practice. Edge 21 has a 10-level path that gets you there step by step.
Is Hi-Lo the best system?
It's the most used because it's simple and performs very well. There are more precise systems (like Zen or Omega II), but they're harder and the difference is small.