Card Counting · Interactive
The Cards That Count for Nothing
A counting tag is only worth as much as it lines up with a card's real effect on your edge. Two explorers below: first, drag the line that splits "low" from "high" and watch the signal rise and fall; then grow the shoe from one deck to twenty and see what stays fixed.
Explorer 1 · Six-deck shoe
Where should the line go?
A balanced count draws one boundary. Cards below it score +1 — a small card has left the shoe, which is good for you. Cards above it score −1 — a big card has left, which is bad. Slide the boundary and watch how tightly the running count tracks your true advantage. The dashed line is standard Hi-Lo, which refuses to score the 7, 8 and 9 at all.
The best single boundary — drawn just after the 8 — scores 0.928. Standard Hi-Lo scores 0.968 by doing less: leaving the three middle cards blank keeps the signal clean.
Explorer 2 · One to twenty decks
Does the number of decks change the answer?
Three counts side by side: standard Hi-Lo, the low-stretch (7-8-9 scored +1, with the small cards) and the high-stretch (7-8-9 scored −1, with the big cards). Grow the shoe and look for a crossing. There isn't one — the order is locked. What changes is the size of the prize.
Ordering and gaps come from each count's betting correlation — exact, and itself almost unchanged by deck count (the single-deck and six-deck effect-of-removal patterns correlate above 0.999). The decline is a counting fact: in a deeper shoe each removed card barely moves the mix, so favorable moments grow rarer and milder — true-count swings shrink roughly like one over the square root of the deck count. Heights are a relative index (standard Hi-Lo at one deck = 100), not a dollar figure; real edges also turn on penetration, bet spread and house rules.