Doubling at the blackjack table: one card, twice the play chips

You hold 6♥ 5♣, the dealer shows 9♠, and next to Hit and Stand there is a third button: Double. What happens when you press it, and what does it do to your play chips? Here are the mechanics and the arithmetic, with real hands.

Blackjack on Card Lounge uses play chips only. You start with 1,000, and if your stack drops below the smallest bet, Reset chips fills it back up to 1,000. Nothing can be bought or won. This note explains rules and numbers; it is not betting advice, and no way of playing guarantees a result.

What Double does

On Card Lounge blackjack, Double follows three rules:

1. First two cards only. Once you have hit, the button is gone. A three-card 11 such as 3♥ 5♣ 3♦ cannot be doubled.
2. The bet is doubled. A second stake equal to your bet leaves your stack, so a 50-chip bet becomes 100.
3. Exactly one more card. You receive one card and your hand is finished. If that card takes you over 21, you lose at once. Otherwise the dealer plays by the usual rule: draw to 16, stand on all 17s, including soft 17.

Splitting and insurance are not offered in this edition, so Double is the only choice besides Hit and Stand. Bets are 10, 20, 50 or 100 chips, so a doubled bet is 20, 40, 100 or 200.

When the button is missing

Double also needs chips. Your bet leaves your stack at the deal, and the button appears only if what remains covers a second stake of the same size.

• 150 chips, bet 100: after the deal 50 remain, less than 100, so there is no Double.
• 150 chips, bet 50: after the deal 100 remain, so Double is offered.

Nor does it appear when the round ends straight after the deal: a blackjack for you, or a dealer blackjack behind an Ace or ten-value card.

The chip arithmetic

A doubled hand is settled like any other, with the bigger bet: a win pays 1 to 1, a push returns the bet, a loss loses it. For a 50-chip bet doubled to 100:

• Win: your 100 comes back plus 100, so you finish 100 chips up.
• Push: your 100 comes back, and you are level.
• Loss: the 100 is gone.

A doubled 21 has three cards, so it is never a blackjack: it pays 1 to 1, not 3 to 2.

Four worked hands

Each hand starts from 1,000 chips.

A win. You bet 50 (950 left) and hold 6♥ 5♣, a hard 11, against the dealer's 9♠. You double: another 50 goes in (900 left) and the bet is 100. Your one card is 10♦, for 21. The dealer turns over 8♣, making 17, and stands. You win 100, and your balance is 1,100.

The dealer busts. You bet 20 and hold 7♦ 3♠, a hard 10, against 6♣. You double to 40 and draw 2♥: a hard 12, and no more cards. The dealer has 6♣ K♦, a hard 16, draws 9♠ and busts with 25. You win 40, and your balance is 1,040: the 12 won only because the dealer went over.

A push. You bet 100 and hold 8♠ 3♥ against 10♣. The dealer checks for blackjack and play continues. You double to 200 and draw 9♦ for 20. The dealer's face-down card is Q♥, also 20. Push: the 200 comes back and you finish at 1,000.

An Ace that counts 1. Same start as the first hand, but the one card is A♦. Counting it as 11 would make 22, so it counts 1: a hard 12. The dealer has 17, you lose the doubled 100, and your balance is 900.

Which hands can bust on the one card

• A hard total of 11 or less cannot bust: no card is worth more than 10.
• A soft hand cannot bust either: the Ace drops from 11 to 1.
• A hard 12 or more can. Double 9♣ 4♦, a hard 13, on a 20-chip bet, draw K♠ for 23, and the 40 chips are lost at once, without the dealer drawing.

What the Hint suggests

Hint highlights one action for your hand. It suggests Double in only two situations: a hard 11 against any dealer card, and a hard 10 against a dealer 2 to 9. It never suggests doubling a soft hand or a 9, and when Double is not available, the same hard 10s and 11s get Hit instead.

The arithmetic of one card shows what to expect. In the first worked hand, 6♥, 5♣ and 9♠ were visible, so a fresh shoe of 312 leaves 309 unseen, the dealer's face-down card included. 96 are ten-value, so the one card makes 21 with chance 96 ÷ 309 ≈ 31.1%; adding the 23 unseen nines (for 20) gives 119 ÷ 309 ≈ 38.5%. Most of the time the card lands lower, as in the second and fourth hands. The hint is a fixed rule of thumb, not a promise.

Try it

1. You have 1,000 chips, bet 20, double a hard 11, and the hand is a push. What is your balance?
2. You have 120 chips and bet 100. Is Double offered?

Answers: 1) 1,000. 2) No: only 20 chips remain after the deal.

For hard and soft totals and the dealer's rule, read Soft 17 explained, and look up terms such as push in the glossary.