Blackjack Edge: Card Counting

NEW — VERIFY YOUR OWN SYSTEM Build a counting system in the editor, then find out what edge it actually produces. Verify System (menu → Tools) deals hands against your system — your tag values, your index plays, your bet ramp, your table rules, your penetration — and measures the edge it really produces. A phone can only deal so many hands in a wait you would tolerate, so every result is a RANGE rather than a single number. The range is the honest answer, and it narrows the longer you run. Runs pool, and if you keep running until you like the answer the app says so on the result itself rather than letting you read it as a guarantee it can no longer make. If it still includes zero, the app says so in plain words instead of printing a figure the run cannot support. It also tells you what a tighter answer would cost in minutes, timed on your own device. Run it once and Bankroll Tools picks it up: your measured edge and variance now drive Risk of Ruin, SCORE, N0 and the bankroll breakpoints. Change your system or your table rules and the app marks the old measurement out of date rather than quietly using it. The figures assume you play every hand. Back-counting is not modelled, so a wonging player does better than the number you see. CORRECTED — RISK OF RUIN AND BANKROLL REQUIREMENTS The two constants behind these figures were not two measurements of the same quantity, and combining them the way the app did overstated risk. Risk of Ruin now reads LOWER and required bankrolls read SMALLER. At the default $10,000 bankroll and $100 max bet on Hi-Lo, Risk of Ruin goes from 27.1% to 3.4%, and the bankroll for 1% Risk of Ruin from $35,306 to $13,632. If you recorded figures from an earlier version, they will differ. The new ones are measured — 20 million simulated rounds per built-in system, seeded and reproducible — not quoted. SCORE moves too, from about 49 to about 29 for Hi-Lo, because it is now computed from that same measured pair rather than from the mismatched one. It is consistent with an initial-bet advantage of 1.02%, which is where this game sits: at a 1-12 spread, that advantage and this SCORE are the same fact stated twice. Insurance is now modelled as well. It is a rule of the game rather than a play style, so leaving it out had been understating every system that specifies an insurance threshold.