Hi-Lo Card Counting: A Complete Beginner's Guide

By CardCount Academy · Reviewed September 24, 2026 · 9 min read

Hi-Lo is the most widely taught card counting system. It is a balanced, level-one count: every tag is +1, 0 or −1, and a full deck adds up to exactly zero. According to the Wizard of Odds, it was first introduced in 1963 by Harvey Dubner. It is simple enough to learn in an afternoon and strong enough that many experienced players never switch.

Before you start: select Hi-Lo in the menu at the top of the site so every drill and quiz uses these values.

Step 1: Learn the values

Five ranks count +1 and five count −1 (tens, jacks, queens, kings and aces), so a deck has twenty +1 cards and twenty −1 cards. That is why a complete deck adds up to zero — a handy self-check: count down a full deck and you should finish at 0.

Step 2: Keep the running count

Start at 0 after every shuffle and add each card's tag as it appears — yours, other players' and the dealer's, including the dealer's hole card once it is turned over. Group cards instead of counting one by one: a 4 and a queen cancel out; three low cards and a king are +2.

Example: a round shows 5, 3, J, 8, 2, A, 6. Tags: +1, +1, −1, 0, +1, −1, +1. Running count: +2.

Practice until you can count a shuffled deck down to zero in about 25–30 seconds without mistakes. Accuracy first; speed follows.

Step 3: Convert to the true count

Divide the running count by the number of decks remaining. A running count of +8 with 4 decks left is a true count of +2. See running count vs. true count for rounding and deck estimation.

A widely used rule of thumb is that each point of Hi-Lo true count shifts the player's expectation by roughly half a percent. Since a typical six-deck game starts with a small house edge, the player usually only gains an advantage somewhere around a true count of +1 to +2 — which is why bet ramps start rising there. The exact figures depend on the rules.

Step 4: Size your bets

Your bet should follow the true count. Our quizzes and simulator use this simple 1–8 teaching ramp:

This ramp is a learning tool, not advice. Real bet sizing depends on the rules, penetration, your bankroll and your tolerance for risk, and large bet swings are exactly what casinos watch for.

Step 5: Add the most important deviations

Basic strategy assumes a neutral shoe. At some counts a different play becomes better. The best-known set of these index plays is the "Illustrious 18" published by Don Schlesinger. The simulator on this site uses these Hi-Lo indexes:

• Take insurance at TC ≥ +3
• Stand 16 vs 10 at TC ≥ 0
• Stand 15 vs 10 at TC ≥ +4
• Stand 12 vs 3 at TC ≥ +2
• Stand 12 vs 2 at TC ≥ +3
• Double 10 vs 10 at TC ≥ +4
• Double 11 vs A at TC ≥ +1
• Stand 16 vs 9 at TC ≥ +5
• Double 9 vs 2 at TC ≥ +1
• Hit 13 vs 2 at TC ≤ −1

"TC ≥ +4" means make the play when the true count is +4 or higher; below it, follow basic strategy. Published index numbers differ slightly between sources and rule sets. Learn insurance and 16 vs. 10 first — they come up often and matter most.

Common Hi-Lo mistakes

• Counting 7s, 8s or 9s. They are 0 — skip them entirely.
• Forgetting the dealer's hole card, or cards burned face up.
• Betting from the running count instead of the true count.
• Learning deviations before basic strategy is automatic.

Your practice plan

1. Values until instant: the values drill.
2. Pairs and full rounds: the cancellations drill, then sequences at a faster pace.
3. Conversion and bets: the true count quiz and betting quiz.
4. Everything together: the simulator in training mode, then exam mode.

Sources and further reading

• Wizard of Odds — Introduction to the High-Low Card Counting Strategy
• Stanford Wong, Professional Blackjack (Pi Yee Press).
• Don Schlesinger, Blackjack Attack: Playing the Pros' Way (RGE Publishing) — origin of the "Illustrious 18".
• Edward O. Thorp, Beat the Dealer (1962; revised 1966).