Basic strategy chart
The best first action for every starting hand, generated from the same engine as the rest of the site. Find your hand in the left column and the dealer's upcard along the top.
Hard totals
Hard 18 through 21: always stand, against everything.
Soft totals
Pairs
The two rules worth memorizing first: always split aces and 8s; never split 10s or 5s.
How often does the dealer bust?
The chart above makes more sense with this table in mind - you stand on weak totals against 4, 5 and 6 precisely because the dealer breaks most often from those cards.
How to memorize the chart
Nobody learns this grid cell by cell. Learn it in layers, and each layer is small.
Start with the four absolutes: always split aces and 8s, never split 10s or 5s, always stand on hard 17 or more, always hit hard 8 or less. Next, learn the stiff-hand rule that covers most of the hard section: with hard 12 through 16, stand when the dealer shows 2 through 6 and hit when the dealer shows 7 or higher, with one exception (hit 12 against a 2 or 3). Then add the doubles: 11 doubles against everything but an Ace, 10 doubles against 2 through 9, and 9 doubles against 3 through 6. That handles the vast majority of hands you will actually be dealt.
The soft totals and remaining pairs come last, and the analyzer is the fastest teacher there: deal yourself the hand, read the numbers, and the logic sticks better than memorization ever does.
Why the chart looks the way it does
Notice the cliff between the dealer's 6 and 7. To the left the chart is full of stands, doubles and splits; to the right it turns into hits. That line is the dealer bust table made visible. Against 2 through 6 the dealer must draw from a breakable total, so you avoid busting first and press bets while the risk is on the house. Against 7 and up the dealer usually finishes with a made hand, so you must improve your own total even at the risk of breaking.