The setup and the goal
- Two players. Each is dealt ten cards; the next card is turned face-up to start the discard pile, and the rest form the face-down stock.
- On your turn, take one card — either the top of the discard pile or the top of the stock — then discard one card face-up.
- The goal is to arrange your hand into melds: sets (three or four cards of the same rank) and runs (three or more consecutive cards of the same suit, such as 5-6-7 of hearts).
- Aces are low: A-2-3 is a valid run, but Q-K-A is not.
Deadwood — the number that decides the hand
Whatever is left in your hand after your melds is deadwood, and it is counted at face value — aces 1, face cards 10. The entire game is a negotiation with that number. You may end the hand by knocking when your deadwood is ten points or fewer.
Ten points or fewer is the knock threshold in standard Gin Rummy. It is worth memorising the combinations: one face card plus nothing else, two mid cards, or a handful of low cards all qualify.
The knock
- On your turn, after drawing and before discarding, you may knock if your deadwood is 10 or less. You lay your melds down and end the hand with your discard.
- Your opponent then lays down their own melds — and may lay off matching cards onto yours, which reduces their deadwood.
- The score is the difference between the two deadwood counts: you score that number if your total is lower.
- If the opponent’s deadwood is equal or lower after laying off, that is an undercut: they score the difference plus a 25-point bonus.
Going gin is the purer version of the same move: knocking with zero deadwood, every card in your hand melted into sets and runs. Gin ends the hand immediately, the opponent cannot lay off anything, and it earns a 25-point bonus on top of their deadwood.
Scoring a game
Hands are played until one player passes 100 points. A hand scores: the deadwood difference (or the undercut in reverse), plus 25 for gin, plus 25 for an undercut. Many score sheets also add a 25-point box bonus per hand won and a shutout bonus for a shutout game — house rules vary, but the difference-and-bonus core never changes.
A worked hand
You hold 7-8-9 of clubs, three nines, and four loose cards: a king, a queen, a four and a two. Your deadwood is 26 — too high to knock. Over the next few turns you trade the king away, draw a five to run 4-5-6, and now only the queen remains loose: 10 deadwood exactly. On your next turn, you knock, your opponent lays off nothing helpful, and the count shows them at 23. You score the 13-point difference and the hand is over.
The rules are that complete. The judgement — which discards are safe, when to knock early, when to hold out for gin — is where the game is actually played, and it is covered in Gin Rummy strategy. Deal a hand on Gin Rummy, or see how the partnership version of card games works in How to play Spades.
