Gin Rummy - Scoring

Scoring

Aces are scored at 1 point, face cards at 10, and all other cards are scored at their numerical values. The number of points awarded for bonuses may vary from region to region. No matter what the bonus amounts are, points are scored in Gin for the following:

Knock Points
After a player knocks, and the lay offs are made, the knocking player receives a score equal to the difference between the two hands. For example, if a player knocks with 8, and the defender has 10 deadwood points in his or her hand after laying off, the knocking player receives 2 points for the hand.
Gin Bonus
After going gin, a player receives a bonus of 25 points plus the entire count of deadwood in his opponent's hand. There is no chance to lay off when a player goes gin.
Undercut (or underknocking)
Occurs when the defending player has a deadwood count lower than or equal to that of the knocking player (this can occur either naturally or by laying off after a knock). In this case, the defender scores an undercut bonus of 25 points plus the difference between the two hands. (In some rule sets, the bonus is only 10 or 20 points, or is not awarded in case of a tie.)
Game Bonus
Once a player has acquired 100 points (or some other agreed-upon number) the match is over, and that player receives a game bonus of 100 points (or another agreed-upon number).
Line Bonus or Box Bonus
Added at the end of the match. For every hand a player won during the match, 25 points is added to their score.
Big Gin
Prior to knocking, if all 11 cards in a player's hand form a legal gin, the player can retain the extra card as part of his hand, and is awarded 31 points plus entire count of deadwood in his opponent's hand. (In some rule sets players may be awarded 50 points or another established amount plus the entire count of deadwood in the opponent's hand)
Shutout Bonus
If a match is completed with the winner having won every hand, the points for each hand are doubled before adding the line bonus.

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