Basic Strategy

The mathematically optimal play for every blackjack situation. Memorize this and the house edge drops to under 0.5%. Click any cell for an explanation.

H = HitS = StandD = DoubleDS = Dbl/StdR = SurrenderSP = Split

Hard Totals

When you have no Ace (or Ace counts as 1)

Hand	2	3	4	5	6	7	8	9	10	A
8
9
10
11
12
13
14
15
16
17

Soft Totals

When one of your cards is an Ace counting as 11

Hand	2	3	4	5	6	7	8	9	10	A
A,2
A,3
A,4
A,5
A,6
A,7
A,8
A,9

Pairs

When your two cards have the same value

Hand	2	3	4	5	6	7	8	9	10	A
2,2
3,3
4,4
5,5
6,6
7,7
8,8
9,9
10,10
A,A

Common Mistakes

Things beginners get wrong — and what basic strategy says instead.

✗Standing on 16 vs dealer 7–A

Hit. Your 16 vs a strong dealer card will lose more often by standing than by taking a card and risking a bust.

✗Never splitting 8s

Always split 8s — even vs a 10. A hard 16 is the worst hand in blackjack. Each 8 becomes the foundation for a better hand.

✗Splitting 10s

Never split 10s. A hard 20 wins ~86% of the time. Splitting breaks one of the best hands into two mediocre ones.

✗Taking insurance

Insurance pays 2:1 but the true odds are worse (~9:4 against). The house has a ~7.5% edge on the insurance bet — always decline.

✗Standing on soft 17 (A,6)

Hit or double on soft 17. You can't bust on one card, and standing gives you only a 17 — often a losing hand.

✗Not doubling on 11

Double on 11 vs dealer 2–10. You have the highest chance of drawing a 10-value card, turning 11 into 21. Maximize your bet here.

✗Hitting hard 12 vs dealer 4–6

Stand. The dealer is in the bust zone (4, 5, 6). Let them bust — taking a card risks busting yourself for no reason.

✗Using a betting system (Martingale)

Betting systems don't change the odds. Doubling after losses chases losses with increasing risk — it has no mathematical advantage.

Rule Variations & House Edge

Rule	Effect on House Edge
Blackjack pays 3:2	−1.4% (player favored)
Blackjack pays 6:5	+1.4% (devastating — avoid!)
Dealer stands soft 17 (S17)	−0.2% vs H17
Late surrender allowed	−0.07%
Double After Split (DAS)	−0.14%
6 decks vs 1 deck	+0.46%
Perfect basic strategy	Total ≈ 0.5% house edge