Gambling terms, explained straight

Advantage Play & Game Integrity

Hi-lo card counting

Hi-lo card counting is a blackjack advantage-play method that tracks exposed cards by giving them a value of +1, 0, or -1, then uses that running total to estimate how many high cards remain in the deck.

Tags
2–6 = +1; 7–9 = 0; 10, J, Q, K, A = −11
Level
Level-1 count (running count changes by at most one per card)2
Introduced
1963 by Harvey Dubner1
True count
Running count ÷ decks remaining1

Key points

  • The counter starts at 0 and adds or subtracts the tag value of each exposed card as it appears.1
  • The running count is divided by the number of decks remaining to produce a true count, which guides betting and playing decisions.1
  • Hi-lo is a level-1 count, meaning the running count changes by at most one per card, making it easier to learn than multi-level systems.2
  • The true count can also be used with index numbers to deviate from basic strategy on certain hands.1

Hi-lo card values

Standard hi-lo tags for each card rank.
Card rank Tag
2, 3, 4, 5, 6+1
7, 8, 90
10, J, Q, K, A−1

Where this term is used

Advantage play Hi-lo blackjack card counting Covers the same system with a focus on blackjack-specific application. Advantage play Card counting The broader class of methods that track exposed cards to estimate deck composition. Advantage play Blackjack card counting General blackjack card-counting techniques, of which hi-lo is one example. Advantage play Card counting machine A device that automates card counting, distinct from manual systems like hi-lo. Advantage play KO card counting An unbalanced card-counting system that eliminates the need for a true count conversion. Advantage play Edge sorting Edge sorting is an advantage-play technique in

Sources

  1. Introduction to the High-Low Card Counting Strategy wizardofodds.com Provides the standard hi-lo tags, the history of Harvey Dubner, and the method for calculating true count.
  2. Card counting - Wikipedia en.wikipedia.org Confirms hi-lo as a level-1 count and the broader context of card counting.

Sources are drawn from regulators, universities and published research, and each one is labelled with what it actually is — a preprint is not called a paper. Bookmaker and affiliate pages are never cited here, because a page that sells betting is not a neutral authority on it.

Written and maintained by Ellis Warrender, writer and maintainer.

Last updated 28 July 2026. Spotted an error? Tell me and it gets fixed and logged on the corrections page.