Rules of International Game

The general rule is that all moves and captures are made diagonally. All references to squares refer to the dark squares only. The main differences from Standard US Checkers are: the size of the board (10×10), pieces can also capture backward (not only forward), the long-range moving and capturing capability of kings, and the requirement that the maximum number of men be captured whenever a player has capturing options.

Starting position

The game is played on a board with 10×10 squares, alternately dark and light. The lower-left square should be dark.
Each player has 20 pieces. In the starting position the pieces are placed on the first four rows closest to the players. This leaves two central rows empty.

Moves and captures

The player with the light pieces makes the first move. The two players make moves alternately.
Ordinary pieces move forward one square diagonally to a square that is not occupied by another piece.
Opposing pieces can and must be captured by jumping over the opposing piece, two squares. If one has the possibility to capture a piece then this must be done even if it is disadvantageous.
- If there is one unoccupied square before or behind opposing pieces then jumps multiple times over opposing pieces in a single turn forward or backward can and must be made, making angles of 90 degrees. It is compulsory to jump over as many pieces as possible. One must play with the piece that can make the maximum captures.
- After the piece has jumped over the opponent's piece or pieces, the jumped-over pieces are taken from the board. The pieces are not removed during the jumping move, only after the entire move is completed.
- The same piece may not be jumped over twice.

Crowning

A piece is crowned if it stops on the far edge of the board at the end of its turn (that is, not if it reaches the edge but must then jump another piece backward). Another piece is placed on top of it to mark it. Crowned pieces, sometimes called kings, can move freely multiple steps in any direction and may jump over and hence capture an opponent piece some distance away and choose where to stop afterwards, but must still capture the maximum number of pieces possible.

Winning and draws

A player with no valid move remaining loses. This is the case if the player either has no pieces left or if a player's pieces are obstructed from making a legal move by the pieces of the opponent.
A game is a draw if neither opponent has the possibility to win the game.
The game is considered a draw when the same position repeats itself for the third time (not necessarily consecutive), with the same player having the move each time.
A one king against one king endgame is automatically declared a draw, as is any other position proven to be a draw.


These are extra rules accommodated in some tournaments and may vary:
- If, during 25 moves, there were only king movements, without piece movements or jumps, the game is considered a draw.
- If there are only three kings, two kings and a piece, or a king and two pieces against a king, the game will be considered a draw after the two players have each played 16 turns.

Rules of Standard US Checkers

The game is played on an 8×8 square board (with sixty-four total squares) with twelve pieces on each side. The pieces move and capture diagonally. They may only move forward until they reach the opposite end of the board, when they are crowned and may thereafter move and capture both backward and forward.

Starting position

Each player starts with twelve pieces on the dark squares of the three rows closest to that player's side. The row closest to each player is called the crownhead or kings row. The player with the darker coloured pieces moves first.

Move rules

There are two different ways to make a move :
- A simple move consists of sliding a piece one square diagonally to an adjacent unoccupied dark square. Uncrowned pieces may move only diagonally forward; kings may move in any diagonal direction.
- A jump is a move from a square diagonally adjacent to an opponent's piece to an empty square immediately beyond it, in the same line. (Thus, jumping over the square containing the opponent's piece.) Uncrowned pieces may jump only diagonally forward; kings may jump in any diagonal direction. A jumped piece is considered captured and removed from the game. Any piece, whether crowned or not, may jump a king.
Multiple jumps are possible if after one jump, another piece is immediately eligible to be jumped, even if that jump is in a different diagonal direction. If more than one multiple-jump move is available, the player may choose which piece to jump with, and which jumping option or sequence of jumps to make. The jumping sequence chosen is not required to be the one which maximizes the number of jumps in the move turn; however, a player must make all available jumps in the sequence chosen.
Jumping is always mandatory: if a player has the option to jump, he must take it, even if doing so results in disadvantage for the jumping player. (For example, a single jump might set up a player such that the opponent has a multi-jump move in reply.)

Kings

If a player's piece moves into the kings row on the opposing player's side of the board, that piece is said to be crowned (or often kinged in the U.S.), becoming a king and gaining the ability to move both forward and backward. If a player's piece jumps into the kings' row, the current move terminates; the piece cannot continue on by jumping back out (as in a multiple jump), until the next move. A piece is normally crowned by placing a second piece on top of it; some sets have pieces with a crown molded, engraved or painted on one side, allowing the player to simply turn the piece over or to place the crown-side up on the crowned piece, further differentiating kings from ordinary pieces.

End of game

A player wins by capturing all of the opponent's pieces or by leaving the opponent with no legal move. The game ends in a draw if neither side can force a win, or by agreement (one side offering a draw, the other accepting).