A chess variant is any game derived from, related to or similar to chess in at least one respect. The difference from chess can include one or more of the following:

• Different board (larger or smaller, another board form, e.g. hexagonal or circle).
• Fairy pieces , different from those used in chess.
• Different rules for capture, move order, game goal, etc.

The national chess variants like xiangqi and shogi are traditionally also called chess variants in western world. They have many similarities with chess and share a common ancestor.

The number of possible chess variants is unlimited. D.B. Pritchard , the author of Encyclopedia of Chess Variants , estimates that there are more than a couple thousand chess variants, confining the number to published ones. The creation in 1998 of Zillions of Games , a Windows compatible software program which enables non-programmers to design and playtest some types of chess variants using an AI opponent, has helped increase chess variant growth within communities that use it.

• Chess with different starting position
• Chess with different board
• Chess with unusual rules
• Chess with incomplete information and/or elements of chance
• Multimove variants
• Multiplayer variants
• Chess with unusual pieces
• Games inspired by chess

Also other variants:
Chinese Chess
Korean Chess