What knocking means
Knocking is a way to end the hand when your deadwood is low enough. Instead of waiting for Gin, you reveal your hand and compare deadwood totals.
When you can knock
You can normally knock when your deadwood is greater than 0 and at or below the knock limit. Many games use a knock limit of 10, but your app can support configurable house rules.
Layoff after a knock
After a normal knock, the defender may be allowed to lay off deadwood cards onto the knocker’s melds. This can reduce the defender’s deadwood and sometimes cause an undercut.
Undercut risk
If the defender has deadwood less than or equal to the knocker’s deadwood after layoff, the defender scores an undercut bonus. That makes low-but-not-great knocks risky.
Knocking tips
Knock when you have a strong read that your opponent has higher deadwood, or when waiting for Gin is too risky. Be careful knocking if your melds create easy layoff opportunities for your opponent.
Next steps
Next, compare knock outcomes with Gin, Big Gin, and undercut scoring, or return to the Learn page.
Frequently Asked Questions
Can you knock with zero deadwood?
Zero deadwood is Gin, not a normal knock. The UI should show GIN! when the current player has zero deadwood.
What happens if both players have the same deadwood after a knock?
The defender undercuts the knocker. A tie counts as an undercut.
Is knocking always better than waiting?
No. Knocking can be safer than waiting for Gin, but it can also backfire if the opponent undercuts you.