Basic strategy is not one chart. It changes with the deck count and the house rules, and most charts online do not say which game they were built for.
Basic strategy is the mathematically correct decision for every hand you can be dealt against every dealer up card, worked out by playing each situation through to the end and taking whichever choice loses least. Follow it perfectly and the house edge drops to roughly half a percent. Play on instinct and you give most of that back.
The part almost nobody mentions is that there is no single chart. The correct play changes with the number of decks and the house rules. A chart built for a six deck game where the dealer stands on soft 17 will give you wrong answers at a double deck table where the dealer hits it.
Blackjack paying six to five instead of three to two does not change which play is correct. It changes how much the game costs you, by roughly 1.4 percent, which is far more than any strategy error you are likely to make.
Look for the rules it was built for, stated on the chart itself. Deck count, soft 17 behaviour, whether doubling after split is allowed, whether surrender exists. A chart that does not say is a chart you cannot use, because you have no way of knowing which game it fits.
Then check the table you are actually sitting at. The soft 17 rule is usually printed on the felt. The rest is in the game information panel online.
Our trainer holds forty ruleset combinations and grades you against the correct chart for the one you select, rather than a single generic table.
We built our strategy data from two independent published sources and compared every cell. Out of 14,400 decisions they agreed on all but one.
The exception is a pair of eights against a dealer ace, in a two deck game where the dealer hits soft 17 and late surrender is available. One source says surrender. The other says split. The expected values are close enough that the answer depends on assumptions neither source spells out.
We show both rather than picking one and pretending there was never a question.
| Rule | Typical effect on house edge | Changes which play is correct | Where to check it |
|---|---|---|---|
| Dealer hits soft 17 | Around 0.2 percent worse for you | Yes, several hands | Printed on the felt or in the game rules |
| Number of decks | Fewer decks favour you | Yes, doubling and splitting | Game information panel |
| Double after split allowed | Around 0.14 percent better for you | Yes, splitting decisions | Game rules |
| Blackjack pays 6 to 5 | Around 1.4 percent worse for you | No | Printed on the felt |
Figures are the commonly published values for a six deck shoe game and vary slightly by exact ruleset.
No. The correct play depends on the deck count and the house rules. A chart that does not state which game it was built for cannot be relied on.
It brings the house edge down to around half a percent. Most casual players give up considerably more than that through instinct decisions.
No, but it costs you around 1.4 percent, which is far more than any single strategy mistake. It is a table to avoid rather than a chart to relearn.
Verified against 2 primary sources. Last reviewed September 10, 2026.