Rule variations

Basic strategy is specific to the rules in force. PlayCorrect covers 32 combinations of decks, dealer soft 17, double-after-split, and late surrender. This page lists what the chips change, what we keep fixed, and a few cells that actually flip. Educational, 21+, not gambling advice.

What the chips change

Decks (1, 2, 6, 8). Six- and eight-deck S17 DAS charts are very close; in our checks on 10 Nov 2026, both matched the same Wizard of Odds “4 or more decks” chart 350/350 for every DAS/surrender/H17 combination we ran. One- and two-deck games change some close cells. Under S17 DAS, no surrender:

• Hard 9 vs 2 is a hit in six or eight decks (hit +0.0772, double +0.0700) and a double in one or two decks.
• 11 vs ace is a hit in six or eight decks S17 and a double in one or two decks S17.
• 6,6 vs 7 and 7,7 vs 8 are hits in six-deck S17 and splits in one- and two-deck S17 DAS.
• Soft 18 vs ace is a hit in two, six, and eight decks S17, and a stand in one-deck S17 (stand −0.1010, hit slightly worse). See soft 18.

S17 vs H17. If the dealer hits soft 17, a few player cells become more aggressive. In six-deck DAS, no surrender, 11 vs ace flips from hit to double, A,7 vs 2 flips from stand to double-else-stand, and A,8 vs 6 flips from stand to double-else-stand. Late surrender also adds hard 15 vs ace and hard 17 vs ace (surrender-else-stand) under six-deck H17, and can turn 8,8 vs ace into surrender-else-split. Those six- and eight-deck H17 charts, including late surrender, matched Wizard of Odds 350/350 on 10 Nov 2026.

DAS on or off. Double after split is why 4,4 vs 5 or 6 is a split in the default set (split EV +0.1102 vs hit +0.0836 vs 5). Without DAS, those hands are usually hit as a hard 8. Other small pairs (2s, 3s, 6s) also lose some split cells when DAS is off. Our six- and eight-deck no-DAS charts matched Wizard of Odds 350/350 on 10 Nov 2026.

Late surrender. When it is offered after the peek, six-deck S17 surrenders hard 16 vs 9, 10, and ace, and hard 15 vs 10, otherwise hitting — but not a pair of eights, which stays a split (split EV −0.3647 vs surrender −0.5000 vs ace). One-deck late surrender is a little different: 15 vs 10 stays a hit on the chart (some compositions prefer surrender; see exact-card notes), and 16 vs 9 stays a hit. Details on 16 vs 10 and 15 vs 10.

What we keep fixed

• US peek: the dealer checks for blackjack with an ace or ten up. Player EVs are conditional on the dealer not having blackjack.
• Double any first two cards.
• Split to four hands; resplit aces is off; split aces receive one card only (a ten then is 21, not a 3:2 natural).
• Blackjack pays 3 to 2.
• Insurance and even money are never taken.

European no-hole-card, resplit aces, and drawing to split aces are not in the chip row. If your table uses those rules, this calculator does not cover it. We also do not cover 6:5 blackjack, Spanish 21, or other side-bet games.

Two close disagreements we did not paper over

On 10 Nov 2026 we compared all 32 tables to the Wizard of Odds strategy calculator (350 cells each). Twenty-nine matched completely. Three tables disagreed in a single close pair cell:

• One-deck H17 DAS, 9,9 vs ace: we stand (stand −0.18613, split −0.18765, margin 0.00152). The Wizard of Odds chart prints split.
• The same cell with late surrender also stands in our table (surrender is −0.500, far worse).
• Two-deck H17 DAS with late surrender, 8,8 vs ace: we split (split −0.49611, surrender −0.50000, margin 0.00389). The Wizard of Odds chart prints surrender-else-split.

Both gaps are small, and our non-ace split EVs use an independence approximation (see about accuracy). We left our computed action in place and recorded the disagreement rather than silently adopting the published cell. The calculator’s rule-mix badge still says “engine-computed (not yet chart-verified)” on those three mixes.

Use the chips that match the table in front of you, and study away from the table. A printed card is the usual aid where the house allows it.