Blackjack glossary

The mathematically best play for every hand, given your cards, the dealer upcard, and the table rules. It minimizes the house edge; it does not overcome it.

The casino’s average profit per dollar wagered, expressed as a percent. Perfect basic strategy on a 3:2 shoe game faces about 0.5%.

Your average result per bet if a situation repeated forever. The hand pages show EV per $100 bet for each play.

A hand with no ace, or an ace that must count as 1. Hard 16 can only be hit or stood on; one more 10-value card busts it.

A hand with an ace counted as 11. Soft 18 (ace-7) cannot bust on one card, which is why you hit it against strong dealer cards.

A hard 12 through 16. One 10-value card busts it, so these are the hands where the dealer’s upcard decides everything.

A hand you would never hit, usually hard 17 or better.

A tie. You keep your bet.

Going over 21. You lose immediately, even if the dealer busts after.

Doubling your bet for exactly one more card. The chart’s ‘double, else hit’ means double when the rules allow it, otherwise hit.

Turning a pair into two hands, matching your bet on the second. Always split aces and 8s; never split 10s or 5s.

Giving up half your bet to end the hand. Late surrender (after the dealer checks for blackjack) is the common form. Early surrender barely exists anymore.

A side bet that the dealer has blackjack when showing an ace. It pays 2:1 on a bet that wins less than 1 in 3 times. Never take it, unless the count says so.

Insurance repackaged: with blackjack against a dealer ace, taking ‘even money’ is the same bad bet as insurance.

The rule letting you double down on hands created by a split. Without it, you split small pairs less often.

Whether the dealer hits soft 17 or stands on all 17s. Hitting soft 17 costs the player about 0.2% and changes a handful of plays.

What a blackjack pays. 3:2 is the standard game; 6:5 adds about 1.4% to the house edge.

The box holding 4 to 8 decks that the dealer pulls cards from.

Single- or double-deck blackjack dealt face down by hand. Different strategy in a few cells, and often 6:5, so check the felt.

Continuous shuffling machine. Cards go back in every hand, which makes counting impossible and speeds up your losses.

How deep into the shoe the dealer goes before shuffling, as a percent. Deeper penetration helps counters; shallow penetration starves them.

The dealer’s visible card and face-down card.

Your total in the Hi-Lo system as cards are dealt: +1 for 2–6, 0 for 7–9, −1 for 10–ace.

Running count divided by decks remaining. This is the number that drives bet sizing and deviations.

The most common counting system. Simple enough to run at table speed, strong enough to beat shoe games.

A spot where the count changes the correct play from basic strategy. The Illustrious 18 are the ones worth learning.

Counting a table without playing, then jumping in when the count goes positive. Named for Stanford Wong.

Casino attention. Bet spreads, session length, and behavior all draw it; getting backed off ends the edge.

The swings. Blackjack’s standard deviation is about 1.15 betting units per hand, which is why counters need big bankrolls.

The number of hands where your expected win equals one standard deviation. Below N0, luck dominates the results.