Hi-Lo is the Honda Civic of card counting systems: not the most sophisticated, not the fastest at top speed, but the easiest to operate correctly under pressure and entirely sufficient for the job. Virtually every professional counter alive learned it first, and many never switched. This post is a complete walkthrough — values, running count, true count, speed drills, and a full shoe example.
The card values
Three categories. Memorize them cold:
- 2, 3, 4, 5, 6 → +1
- 7, 8, 9 → 0
- 10, J, Q, K, A → −1
These are the same across every common Hi-Lo resource — Schlesinger's Blackjack Attack, Stanford Wong's Professional Blackjack, the Wizard of Odds. If anyone's values disagree, their values are wrong.
A useful sanity check: a full single deck sums to zero. Twenty low cards (2–6) at +1 each = +20. Twelve neutral cards (7–9) at 0 = 0. Twenty high cards (10, J, Q, K, A) at −1 each = −20. Total: 0. Deal a whole deck, count it down aloud, and you should finish on 0. If you don't, your count is wrong and you need to practice.
Running count
The running count (RC) is the cumulative sum of Hi-Lo values as cards are dealt. Start at 0 when a fresh shoe is shuffled. Add the value of every card you see — yours, the dealer's, other players'. The dealer's hole card counts only when it's flipped over, not when it's placed face-down.
There is no "reset" during a shoe. The count carries through every hand, every player action, every dealer draw, all the way until the cut card triggers a shuffle. Only then does RC go back to 0.
True count — why RC alone isn't enough
A running count of +6 has different meaning depending on how much shoe is left.
- +6 RC at the top of a 6-deck shoe? +1 per deck. Tiny edge.
- +6 RC with 1 deck left? +6 per deck. Massive edge.
To normalize, divide by the number of decks remaining:
TC = RC ÷ decks remaining.
Decks remaining is estimated by eyeballing the discard tray. Most counters work in half-deck increments — more precision isn't useful because TC thresholds for decisions are integers anyway. If the discard tray looks "about two decks in," in a 6-deck game you have roughly 4 decks left.
Rounding convention
Default Hi-Lo rounding is floor toward zero. TC of +2.7 rounds to +2, TC of −2.7 rounds to −2. This is not Math.floor (which would send −2.7 to −3). Conceptually, you always use the weaker end of the count's range — a conservative choice that keeps you from over-betting a barely-positive count.
Worked rounding examples
| RC | Decks left | Raw TC | Floor toward zero | |---|---|---|---| | +6 | 2 | +3.0 | +3 | | +5 | 1.5 | +3.33 | +3 | | +7 | 1.5 | +4.67 | +4 | | −5 | 1.5 | −3.33 | −3 | | −7 | 1.5 | −4.67 | −4 |
Pairing — the speed trick
Card-by-card counting is fine for beginners, but a table runs 60–100 hands per hour, and you need to track your own hand, the dealer's upcard, other players' actions, and the bet sizes for yourself and them. Your brain doesn't have bandwidth to also run mental arithmetic three times per second.
The speed trick: pair cards that cancel. A +1 and a −1 cancel to 0. If you see a 5 next to a King, you ignore both — they wash. If you see 5, King, 7, 4, you think "+1 −1 0 +1 = +1," but after a few hundred reps you think "wash, +1 … wash … +1." You're pairing visually without consciously calculating.
Intermediate counters pair whenever adjacent cards are opposite signs. Advanced counters use more elaborate mental shorthand. The goal is always the same: let the arithmetic happen in the background while you play the game in the foreground.
A shoe-length worked example
Freshly shuffled 6-deck shoe. We're playing heads-up with the dealer.
Hand 1. Dealer deals: player 7, 10. Dealer upcard: 3. Hole card face down.
- 7 → 0.
- 10 → −1.
- 3 → +1.
RC = 0 (so far). Decks remaining ≈ 6. TC = 0. Bet is flat.
You hit on your 17? No — you stand. Dealer flips hole: 9. Dealer total 12. Dealer draws 6: total 18. Dealer stands.
- 9 (hole) → 0.
- 6 → +1.
RC = +1. Hand over.
Hand 2. Player: 4, 3. Dealer up: K.
- 4 → +1.
- K → −1.
- 3 → +1.
RC = +2. You hit (7 vs K, per basic strategy → you have 7, not 7; let's say you have hard 7, you hit). Draw 10: total 17. Stand.
- 10 (your draw) → −1.
RC = +1. Dealer flips hole: 7. Total 17. Dealer stands. Push.
- 7 (hole) → 0.
RC = +1 after 2 hands.
After 20 hands. Say RC is now +8, and the discard tray looks about 2 decks in. Decks remaining ≈ 4. TC = +8 / 4 = +2. You ramp to 1–2 unit bet.
After 40 hands. RC has climbed to +14, discard tray at 3.5 decks in. Decks remaining = 2.5. TC = 14 / 2.5 = +5.6 → +5. You're at table-max bet for your spread. Hit a deviation? 16 vs 10 stands (index 0). 12 vs 3 stands (index +2). Insurance if dealer shows Ace (index +3).
Cut card. Shuffle. RC resets to 0.
What you don't do: freak out if a good count disappears before you cash in. Variance is real — a +5 TC can collapse to 0 in a few hands. The counter edge is a long-run statistical fact, not a single-hand guarantee.
Practice drills
The bar:
- Speed drill. Deal a full 52-card deck face up one at a time, as fast as you can, and count down to 0. Target: under 25 seconds. Professional counters do it in 15.
- Distraction drill. Same as above, but have music playing, someone talking near you, or a TV on. Counting accurately under noise is a different skill from counting in a quiet room.
- Paired drill. Deal cards in pairs (two face-up at a time). Practice cancelling adjacent pairs. Target: same 25-second bar, but with less conscious arithmetic.
- Shoe drill. Deal 6 decks in a row, counting all the way through, and verify you finish on 0. Aim for 4 minutes without errors.
- Decision drill. In addition to counting, announce the correct basic-strategy play for each hand as it comes up. Both skills must run in parallel at a real table.
Where to go next
Hi-Lo RC and TC are the arithmetic layer of counting. Layered on top:
- Basic strategy. Required foundation. Without it the counting edge doesn't materialize — a mis-played hand costs more EV than a +2 count gains.
- Deviations (Illustrious 18 + Fab 4). Cells of the basic-strategy chart that change action at certain TCs. See our deviations post.
- Bet sizing. Half-Kelly ramp matched to TC. See kelly criterion blackjack.
- Game selection. Pen, rules, and spread tolerance matter more than which system you use. A master Hi-Lo counter at a bad game loses; a Hi-Lo beginner at a great game wins.
Common mistakes to avoid
Dividing by cards instead of decks. TC = RC ÷ decks remaining, never RC ÷ cards remaining. Dividing by cards produces microscopic fractions that don't line up with any published deviation index or bet ramp. If your TC is a tiny fraction, you're using the wrong denominator.
Forgetting to count the dealer's hole card. The hole card is counted when it flips over (usually at the end of the hand when the dealer plays their own cards), not when it's placed face-down at the deal. Counting it twice — once when dealt and once when revealed — is a surprisingly common beginner error.
Rounding inconsistently. Pick floor-toward-zero and stick with it. Mixing between floor, round-to-nearest, and round-up across different decisions quietly breaks your deviation indices without any single error jumping out.
Resetting the count mid-shoe. The count persists across hands until the cut card triggers a shuffle. Only shuffles reset RC to 0. Between hands, between players, through bathroom breaks at the pit — the count keeps running.
Over-converting to TC. Converting RC to TC on every card is exhausting and unnecessary. Convert before bets and at decision points where a deviation might apply. Everywhere else, the running count is your working memory.
Counting without basic strategy. Every basic-strategy mistake costs roughly 0.01–0.05% EV. A counter making 3+ basic errors per hour erases the entire counter edge. Master basic strategy first, then layer counting on top — not the other way around.
Beyond Hi-Lo
More complex systems exist:
- KO (Knock-Out): unbalanced, skips TC conversion. Simpler mental model, slight accuracy loss.
- Hi-Opt II / Omega II: more granular values (+2, +1, 0, −1, −2), higher accuracy for deviations.
- Wong Halves: fractional values, near-optimal correlation, brutal mental load at table speed.
For nearly every counter, Hi-Lo's speed-vs-accuracy tradeoff is the right pick. The marginal EV from a more complex system is often under 5% of the counter edge, while the error rate at table speed tends to be much higher with fractional or multi-level systems. Master Hi-Lo first. Consider upgrading only if you're already running Hi-Lo accurately at 100+ hands/hour and looking for incremental gains.
Ready to benchmark? Our 15-hand test measures your RC accuracy, TC estimation, bet sizing, and action decisions in under five minutes. No account required.