Blackjack card counting
Blackjack card counting, for real, one card at a time
A live Hi-Lo card counting trainer, not another article about counting. Cards deal from a shuffled six-deck shoe, you call each one's value, and the tool tracks your speed and accuracy as you build up from a relaxed pace to full table speed.
Call each card's Hi-Lo value before the next one deals. On auto speeds, a missed answer counts as wrong and the shoe keeps moving, just like a real table.
What is the difference between the running count and the true count?
The running count is the raw Hi-Lo tally; the true count divides it by the number of decks left in the shoe. Hi-Lo is the modern, simplified descendant of the counting systems Edward Thorp, a mathematics professor, first proved out mathematically and published in his 1962 book Beat the Dealer, the book that showed a shoe of cards isn't perfectly random once you've seen part of it. The running count is the simple tally: every time a 2 through 6 appears, add 1, every 10, J, Q, K or ace, subtract 1, and 7, 8 and 9 do nothing. That's the number the drill above tracks card by card. On its own, though, a running count of +8 means something very different in a shoe with six decks left than in one with half a deck left, the same number of extra low cards is a much bigger share of what's left to be dealt. The true count fixes that by dividing the running count by the estimated decks remaining, running count ÷ decks remaining = true count. Use the "Check the count" button above at any point in a drill to see both numbers worked out from where you are in the shoe.
How often is the count high enough to matter?
Not often: in a six-deck shoe the true count reaches +3 on only about 8.6% of rounds. We dealt 100,000 six-deck shoes to 75% penetration and checked the true count at the start of every round, about 4.6 million rounds in all. The count was +1 or higher on 27.8% of them, +2 or higher on 15.5%, and +3 or higher on just 8.6%. It sat at −1 or lower on 46.7%.
So most of the time a counter is waiting, betting the table minimum and playing basic strategy like everyone else. The edge lives in that thin slice of good shoes, and the bet has to jump when it arrives, which is exactly the pattern surveillance looks for. The script is on the research page if you want to change the deck count or penetration.
Hi-Lo card values
| Cards | Hi-Lo value |
|---|---|
| 2, 3, 4, 5, 6 | +1 |
| 7, 8, 9 | 0 |
| 10, J, Q, K, A | -1 |
Is card counting illegal in the UK?
No. Counting cards in your head, using only information dealt face-up in front of you and basic arithmetic, isn't fraud or cheating under UK law or in most regulated markets. What it does breach is the private terms of service almost every casino sets, which means a casino can legally refuse to deal to a suspected counter, limit their bets, or ban them from the property entirely, the same way any business can decline custom. Using an external device or app to count for you is a different matter, and is both against the rules and often against gambling law specifically, unlike counting in your own head.
Counting is not prediction
Set this beside the "AI predictor" apps covered elsewhere on this site and the difference is stark. Card counting doesn't predict anything, it tracks public information, which cards have already been dealt, to update a known probability, using nothing but arithmetic a person can do in their head. That's fundamentally different from a roulette or slot "predictor" claiming to know a future random outcome it has no information about. Counting only works at all because a physical shoe is dealt down without full reshuffling between hands, which is exactly why it doesn't apply to RNG-based online blackjack, and why live-dealer studios that do use a real shoe lean on live dealer AI tracking, computer vision watching every card and shuffle, specifically to catch the pattern of bet sizing that gives a counter away.
Can smart glasses or an app count cards for you?
Technically yes, but any device that counts for you is banned at real tables and can fall under UK cheating law. Technically, a wearable running computer vision to read cards and keep a running count isn't far-fetched, there are demo builds and browser-based simulators online that do exactly this against a video feed, and the same question comes up regularly wherever this gets discussed. It hasn't taken off as a real-table tool for a simple reason: it isn't a maths problem, it's a hardware and detection problem. Physical casinos ban electronic devices, phones and hidden cameras at the table specifically to close this door, and a headset pointed at the cards is about as easy to spot as a phone propped on the felt. That's why this category of build tends to stay in home practice and simulator environments rather than ever reaching a real table, the arithmetic was never the hard part, staying undetected while breaking a device ban is.
Once you've got the raw card values down, the strategy chart is the next layer, since serious counters deviate from basic strategy at specific counts. And every recommendation this drill and the chart are built on ultimately comes from the same source as the Blackjack AI calculator, ready to check a specific hand whenever you want a straight answer instead of a full table.
Building the skill
Counting is a skill you build slowly, and it is only legal when it stays in your head.
FAQ
Card counting FAQ
Is card counting illegal?+
No, not in the UK or most jurisdictions. Counting cards in your head uses only information you can legally see and public arithmetic, it isn't cheating or fraud. What casinos can legally do instead is refuse service or ban a suspected counter from playing, since it's a private business and card counting breaches most casinos' terms even though it isn't a crime.
What's the difference between running count and true count?+
The running count is a simple tally, add 1 for every low card (2-6) dealt, subtract 1 for every high card (10 through ace), and do nothing for 7-9. The true count divides that running count by the number of decks estimated to remain in the shoe, which matters because the same running count means a much stronger advantage in a nearly empty shoe than in a fresh one.
Can card counting beat the house?+
In the right conditions, skilled counters can turn a small edge, typically under 1%, by increasing bets when the true count is high and playing perfect basic strategy throughout. It requires real skill, a large bankroll to survive the swings, and a casino that hasn't restricted the rules or shuffled early enough to shut the technique down, which is common today.
Does card counting work for online blackjack?+
Not against RNG-based online blackjack, which reshuffles a virtual deck after every hand, there's no depleting shoe to track. Live-dealer blackjack streamed from a studio deals from a real, physical shoe like a land-based table, so the underlying maths applies, though studios shuffle frequently and use computer vision tracking specifically to make sustained counting impractical.
How long does it take to learn Hi-Lo counting?+
Most people can learn the Hi-Lo values in a few minutes, they're simple, +1, 0 or -1 per card. Getting fast and accurate enough to count silently at full table speed, several cards a second across multiple hands, typically takes regular drilling over several weeks, which is what a speed-based trainer like the one on this page is for.
Could AI glasses or a computer vision app count cards for you at a real table?+
Technically the counting itself is simple enough that a camera and some computer vision could keep a running count. The obstacle isn't the maths, it's that physical casinos ban electronic devices, phones and hidden cameras at the table specifically to prevent this, and a headset pointed at the cards is easy to spot. That's why this stays a home practice or simulator idea rather than a real-table tool.
Does a continuous shuffling machine stop card counting completely?+
It comes close. A continuous shuffling machine (CSM) reshuffles discards back into play after every hand, which destroys the changing deck composition that counting depends on. A hand-shuffled game or one dealt from a standard shoe between shuffles is still countable in principle. It's one of the main reasons profitable card counting has become far rarer at modern casinos than it was decades ago, regardless of how good the counter is.
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