Wong Halves

Updated 24 August 2026

Wong Halves is level three and uses fractions. It has the highest betting correlation of any common system — and the highest error rate in practice. We computed its betting correlation at 0.993 — against 0.963 for Hi-Lo — from the effect each card has on the game, rather than copying the figure from a book.

How it compares, and how we know

With tags running from −1 to +1½ in half-point steps, Wong Halves tracks the shoe more faithfully than anything else in common use. Many players double every tag to avoid fractions, then halve at the end.

The number that ranks counting systems is betting correlation: how closely the system’s tags track the actual effect each card has on your edge. We computed it rather than copying it — by removing one card of each rank from the shoe, recalculating the entire game, and correlating the result with the tags. The full method is here.

Is it worth switching from Hi-Lo?

Probably not. The gain over Hi-Lo is 0.030 of correlation, which translates into a small fraction of a percent of edge. A single miscount per hour costs more than that.

Who it actually suits: Almost nobody, honestly. Its 0.993 correlation is worth roughly 2.950% more than Hi-Lo — and one miscount an hour costs more than that.

This is the part the system comparisons usually skip. The difference between counting systems is small. The difference between counting accurately and counting sloppily is not.

Every system, with the numbers

Computed for six decks, dealer stands on soft 17, using the effect of removal for each card rank.

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By Martin Kosek · every number on this site is computed by us, not copied.