Counting System · Level 3

The Wong Halves Card Counting System

By VectorLogic · Updated October 2026

Wong Halves is the most precise of the widely used counts. It weights each card by how much it really changes the player's edge, which means half-point tags. It is accurate and demanding: a system for players who already count without mistakes.

Wong Halves at a glance
Level	3 (tags from −1 to +1½)
Balanced	Yes. A full deck counts to 0
True count needed	Yes
Betting correlation	0.99
Playing efficiency	0.56
Insurance correlation	0.72

Wong Halves card values

Wong Halves card tag values, with the doubled whole-number version
Cards	Tag	Doubled
5	+1½	+3
3 · 4 · 6	+1	+2
2 · 7	+½	+1
8	0	0
9	−½	−1
10 · J · Q · K · A	−1	−2

The 5 matters most: removing it helps the player more than any other card, so it gets the biggest tag.

A worked count

Worked Wong Halves running count
Card	Tag	Running count	Doubled count
5	+1½	+1½	+3
2	+½	+2	+4
K	−1	+1	+2
9	−½	+½	+1
7	+½	+1	+2
3	+1	+2	+4

The doubled-tag shortcut

Most Wong Halves players count with the doubled tags so there are no fractions, then halve the result when they convert to a true count. A doubled running count of +4 is a Wong Halves count of +2.

Converting to the true count

Divide the running count by decks remaining, as with Hi-Lo. If you count doubled, divide by decks remaining and then by 2. The true count calculator has a Wong Halves setting that uses its slightly higher edge gain per true count point.

Who Wong Halves suits

Good fit: you already keep Hi-Lo without errors and play shoe games where you can spread your bets widely.
Poor fit: you are still learning, or you play fast games with heavy distraction. The extra precision is lost the moment the count is wrong.

Its betting correlation of 0.99 against Hi-Lo's 0.97 is a real but small gain. See how all seven systems compare on the systems page.

Where Wong Halves came from

Stanford Wong published the Halves count in Professional Blackjack (1975), the same book that made Hi-Lo the standard count.

Sources

WongHalvesSystem.kt in the Counting Edge source: Wong Halves tag values
CountingSystemProfile.kt in the Counting Edge source: bet ramps, starting counts and key counts
Stanford Wong, Professional Blackjack
How this site's figures are checked: About

Frequently asked questions

Is Wong Halves worth learning over Hi-Lo?

Only if you already keep a fast, error-free Hi-Lo count. Wong Halves gains a little betting accuracy (0.99 against 0.97), but a mistake in a harder count costs more than that gain.

How do I avoid counting in halves?

Double every tag so they are whole numbers, then halve the true count at the end. A 5 becomes +3 and a 9 becomes −1.

Is Wong Halves balanced?

Yes. A full deck counts to exactly 0, so you start at 0 and convert to a true count like Hi-Lo.

Practice on Android

Let the App Handle the Halves

Counting Edge counts Wong Halves for you as you tap cards, converts to the true count, and runs timed drills so you can check your own count. Free and open source.

Download APK — Free