Blackjack Rules — How to Play and Keep Score
Blackjack is a banking game: each player is on their own against the dealer, trying to get closer to 21 without going over. The card play is fast and needs no bookkeeping, so what the app tracks is the money. Every hand moves chips between a player and the bank, and the session ends when only one stack is left.
Overview
Blackjack is a banking game: each player is on their own against the dealer, trying to get closer to 21 without going over. The card play is fast and needs no bookkeeping, so what the app tracks is the money. Every hand moves chips between a player and the bank, and the session ends when only one stack is left.
Setup
Agree a starting stack and a usual bet before the first hand. Shuffle the shoe, choose who deals, and give everyone their opening stack in the app. If the deal rotates, the dealer for each hand still plays the bank against everyone else.
How to play
Every player places a bet. The dealer gives two cards to each player and two to themselves, one of the dealer's face up. Cards two through ten count face value, jacks, queens and kings count ten, and an ace counts eleven unless that would bust the hand, in which case it counts one.
Each player in turn hits for more cards or stands. Going over 21 is a bust and the bet is lost straight away, even if the dealer later busts too. When everyone has finished, the dealer reveals their hole card and draws until reaching at least 17. A two-card total of 21 is a natural blackjack and pays a premium.
Scoring
The app never records card totals. It records the change to each player's stack, and every hand is one entry per player.
| Result | Entry |
|---|---|
| Beat the dealer | + the bet |
| Natural blackjack at 3 to 2 | + 1.5 times the bet, rounded down to a whole chip |
| Natural blackjack at 6 to 5 | + 1.2 times the bet, rounded down |
| Lost, or busted | − the bet |
| Push, including two naturals | 0 |
| Surrendered | − half the bet |
Doubling down doubles the stake for that hand, so a win is plus twice the bet and a loss is minus twice. Splitting creates two hands each carrying the original bet, settled separately; a ten on a split ace counts as an ordinary 21, not a natural, and pays even money. Insurance is a separate stake of up to half the main bet: if the dealer has blackjack it pays two to one, which exactly cancels the main bet for a net entry of 0, and if the dealer does not it is simply lost on top of whatever the main hand does.
Running stack is the starting stack plus the sum of all entries. Because entries are frequently negative, the score column must accept minus numbers.
Ending the game
A player whose stack reaches zero, or whatever floor the group set, is out. The last player with chips wins. Groups who dislike knockouts instead fix a number of hands and compare stacks at the end, which is how tournament blackjack works.
Common variations
House games often let a busted player buy back in once. Pontoon and Spanish 21 change enough of the card play to be worth treating as separate games. Several groups pass the bank to whoever wins with a natural, which keeps the dealer's edge circulating.
Scoring at a glance
| Who wins | Last standing |
|---|---|
| Played to | 21 points by default |
| Score sheet | Counting up to or down from a limit |
| Typical round score | -40 – 40 |
| Negative scores | Possible |
| Worth knowing | Enter the change to a player's stack for the hand, not the hand's card total. Plus the stake on a win, plus one and a half stakes on a natural, minus the stake on a loss, zero on a push. |
Blackjack — score sheet
Worked example
Settings: startingStack: 100, defaultStake: 10, eliminationFloor: 0.
Players: Anna, Ben, Cara.
Every cell is the change to that player's stack for the hand — never a card total.
| Hand | Anna | Ben | Cara | What happened |
|---|---|---|---|---|
| 1 | +10 | −10 | +15 | Cara turned a natural, paid 3 to 2 |
| 2 | −20 | −10 | +10 | Anna doubled down and lost |
| 3 | 0 | −20 | +10 | Anna pushed; Ben doubled and lost |
| 4 | −10 | −20 | +20 | Cara split and won both hands |
| 5 | −5 | −20 | +10 | Anna surrendered for half her stake |
| 6 | −10 | −20 | +10 | Ben's last chips |
| 7 | −25 | — | +25 | Ben is out; his cells stop |
| 8 | −40 | — | +40 | Anna's last chips |
Running stacks, which are startingStack plus the entries so far:
| After | Anna | Ben | Cara |
|---|---|---|---|
| 1 | 110 | 90 | 115 |
| 2 | 90 | 80 | 125 |
| 3 | 90 | 60 | 135 |
| 4 | 80 | 40 | 155 |
| 5 | 75 | 20 | 165 |
| 6 | 65 | 0 — out | 175 |
| 7 | 40 | out | 200 |
| 8 | 0 — out | out | 240 |
Expected standings: Cara 240, rank 1 — winner; Anna 0, rank 2; Ben 0, rank 3.
finished: true — one player is left holding chips.
What this catches:
The highest stack leads. Cara wins on 240. This scorer also serves games where the lowest number is the good one, so getting the direction backwards here would hand the session to whoever went broke first and still look like a working scoresheet.
Two players on zero are not tied. Anna and Ben both end on nothing, but Anna ranks above Ben because she survived three hands longer. Eliminated players are ordered by when they went out, most recent first — ranking them by their final stacks would put every bankrupt player in a meaningless tie.
Elimination is a state, and a knocked-out player's later cells are absent. Ben has no entry at all for hands 7 and 8 — not a zero. A zero would mean he sat a hand out with his chips intact, and treating a missing cell as one keeps him in the game forever.
The stack is derived, never stored. Nothing on the sheet holds 240; it is
100 + 15 + 10 + 10 + 20 + 10 + 10 + 25 + 40. Changing the starting stack mid-session
therefore re-values every row at once, which is the whole reason the entries are deltas.
The floor is a setting, not a constant. With eliminationFloor: 20 Ben is out one
hand earlier, at the end of hand 5, because reaching the floor is enough — it does not
have to be passed.
House rules and settings
Every table plays Blackjack a little differently. These are the 11 rules groups argue about. Each one is a setting in the app — and changing it recalculates a match that is already in progress, which is the thing no other score keeper does.
Starting chips each: what is the default in Blackjack?
What every player begins the session with. It can be real chips, matchsticks or just a number on the screen.
Default: 100. Adjustable from 10 to 10000 in steps of 10.
In the app: “Starting chips each”.
Usual bet: what is the default in Blackjack?
The bet the app suggests each hand. Players can always override it for a particular hand.
Default: 10. Adjustable from 1 to 500 in steps of 1.
In the app: “Usual bet”.
Blackjack pays: what are the options in Blackjack?
What a two-card 21 is worth. The classic payout is 3 to 2; the 6 to 5 version is common in casinos now and is much worse for the player.
Default: 3 to 2 (one and a half times the bet). Three options:
In the app: “Blackjack pays”.
Dealer on soft 17: what are the options in Blackjack?
A soft 17 is an ace plus a six, where the ace can count as one or eleven. This decides whether the dealer draws again on that hand.
Default: Dealer stands. Two options:
In the app: “Dealer on soft 17”.
Doubling down allowed: on or off in Blackjack?
Lets a player double their bet after seeing their first two cards, in exchange for taking exactly one more card. Wins and losses are then twice the size.
Default: on.
In the app: “Doubling down allowed”.
Splitting pairs allowed: on or off in Blackjack?
Lets a player who is dealt two cards of the same rank separate them into two hands, each carrying its own bet, and settle them independently.
Default: on.
In the app: “Splitting pairs allowed”.
Surrender: what are the options in Blackjack?
Lets a player give up a bad hand and lose only half their bet. Late surrender is offered after the dealer has checked for blackjack, early surrender before.
Default: Not allowed. Three options:
In the app: “Surrender”.
Insurance offered: on or off in Blackjack?
A side bet of up to half the main bet, available when the dealer shows an ace, paying two to one if the dealer turns out to have blackjack.
Default: off.
In the app: “Insurance offered”.
Who deals: what are the options in Blackjack?
In a home game the dealer's edge matters, so most groups pass the deal round. A fixed banker keeps the maths simple but hands them an advantage.
Default: Rotate each hand. Three options:
In the app: “Who deals”.
Decks in the shoe: what is the default in Blackjack?
How many packs are shuffled together. Fewer decks slightly favour the players.
Default: 6. Adjustable from 1 to 8 in steps of 1.
In the app: “Decks in the shoe”.
Out when chips drop to: what is the default in Blackjack?
A player whose stack reaches this figure or below is knocked out. The last player still holding chips wins the session.
Default: 0. Adjustable from 0 to 1000 in steps of 5.
In the app: “Out when chips drop to”.
Variants of Blackjack
Tournament format
Everyone plays a fixed number of hands with equal stacks. Nobody is knocked out; the biggest stack at the end wins.
Pontoon
The British cousin. The dealer's cards are both face down, a five-card hand under 22 beats everything but a pontoon, and the banker wins ties.
Spanish 21
The tens are stripped out of every deck and a long list of bonus payouts compensates. Player 21 always beats dealer 21.
Blackjack is also known as
Twenty-One, Vingt-et-Un, Pontoon. These are the same game — the rules and the score sheet above apply to all of them.
Keep score offline
The sheet above works in your browser. Cardzo for iPhone remembers your players, survives a closed tab, and works in a field with no signal.
Coming to the App Store.