Basic Strategy, Explained

Basic strategy is the mathematically correct play for every blackjack hand against every dealer upcard. It is the answer to a solved problem. This page explains where it comes from and why it sometimes tells you to do things that feel wrong. If you only want the answers, they are on the strategy chart. If you want them to become reflex, train them on the training table.

Why blackjack is solvable

The dealer has no choices. They hit until 17 and stop. So for any hand you hold, against any upcard, every action you could take has a computable expected value: the average amount you win or lose per dollar bet if the situation repeated forever. Basic strategy is the action with the highest expected value in each situation. Our chart is not copied from a book. Our engine computes those expected values directly, and the trainer uses the same engine to price your mistakes in dollars.

Three examples of the math overruling instinct

16 against a 10: hit. It feels suicidal, because you bust more often than not. But standing wins only when the dealer busts, about 23% of the time from a ten. Hitting is also bad, since 16 vs 10 is the worst hand in blackjack, but it is less bad, by about two cents per dollar. Basic strategy does not promise good outcomes. It promises the least-bad one available.

12 against a 4: stand. Only four ranks bust you (10, J, Q, K), so hitting feels safe. But the dealer's 4 busts about 40% of the time, and your 12 beats nothing the dealer makes. The only way you win standing is a dealer bust, and that is what a 4 offers. Let them fall.

Soft 18 against a 9: hit. Eighteen sounds like a made hand, but against a 9 it loses on average, because the dealer makes 19 or better too often. The ace makes your hand unbustable on the next card, so drawing to improve costs you nothing catastrophic and gains more than it loses.

What basic strategy is worth

With perfect basic strategy at a decent table, the house edge is about half a percent. We measured it at 0.50% over five million simulated hands. Playing by feel typically gives the house an extra one to two percentage points. At $25 a hand, perfect strategy loses about $12 per hundred hands on average, and guessing loses $40 or more. The chart does not beat the game. Only counting can do that, and only under the right conditions. But the chart makes blackjack the cheapest game in the casino.

How to learn it

Do not memorize the chart cell by cell. Learn the patterns. Always stand on hard 17+. Always hit 8 or less. Double 11 against everything at H17 tables, the common game (at S17, hit against the ace). Never split tens or fives. Always split aces and eights. The 12–16 “stiff hands” follow one rule: stand against a weak dealer upcard (2–6), hit against a strong one (7–ace), except 12 vs 2 and 3, which you hit. Then train at the table until it is reflex. It grades every decision instantly and shows what each mistake costs in dollars, so you spend your time on the cells you miss.

Rule variations

A little. H17 tables want a few more doubles. Surrender adds escape hatches for 15s and 16s. Double-after-split makes more pair splits worthwhile. The chart page recomputes for each variant. Pick your table's rules and study that version.