Gin Rummy Knock Rules

In common gin rummy rules, you can knock after drawing and before discarding if your deadwood will be 10 points or less after the discard. You reveal your hand, your opponent reveals theirs, and the lower deadwood total scores.

How To Knock

1. Draw from the stock or discard pile.
2. Arrange as many cards as possible into sets and runs.
3. Check the value of your remaining deadwood.
4. If your deadwood will be 10 or less after discarding, discard and declare the knock.
5. Reveal your melds and deadwood.

Old table rules often used a face-down discard or an actual knock on the table. Browser games usually use a Knock button.

What The Defender Can Do

After a normal knock, the defender may lay off deadwood cards onto the knocker's melds. For example, if the knocker has 5-6-7 of hearts and the defender has the 8 of hearts as deadwood, the defender can lay off that 8 and reduce their deadwood.

The knocker does not get to lay off onto the defender's melds. Layoff only helps the defender.

What Is An Undercut?

An undercut happens when the defender ends with deadwood equal to or lower than the knocker's deadwood. This can happen naturally or after layoff. In that case, the defender wins the hand and scores an undercut bonus.

Knocking Vs. Going Gin

Going gin means you have no deadwood. It is stronger than a normal knock because the defender does not get to lay off. The gin player scores a bonus plus the opponent's deadwood.

Waiting for gin can pay off, but it is risky. Your opponent may knock first with a decent hand and end the round before you finish yours.

When Should You Knock?

• Knock earlier when your deadwood is low and your opponent has been drawing from stock.
• Be more cautious if your opponent has taken several useful discards.
• A low knock, like 1 to 4 deadwood, is harder to undercut.
• A high knock, like 9 or 10 deadwood, can still be right if the opponent looks dangerous.
• Do not wait forever for gin. A good knock often beats a perfect plan.

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