Janggi Chess

About Janggi Chess

Janggi Chess is the Korean version of chess. The board is nine columns by ten rows, slightly different from international chess. The pieces include a general, two horses, two chariots, two elephants, two cannons, two guards, and five soldiers per side. The objective is to checkmate the opposing general, just like international chess, but the piece movements differ.

Janggi has been played in Korea for over a thousand years. It is part of the same family of games as Chinese xiangqi, with which it shares many pieces and concepts. The rules diverge in several places, most notably in the cannon piece, which moves uniquely in each variant.

The general is restricted to a three-by-three palace at the center of each side's home rank. The general cannot leave the palace. This is unlike international chess, where the king can roam the whole board. So the general's role is more passive, defending its position rather than walking out into the field.

The cannon is the most distinctive piece. It moves like a chariot but only over another piece. To capture, the cannon needs to leap over exactly one piece, friendly or enemy, in its line of fire. The cannon cannot capture another cannon. These rules make cannons uniquely positional. Their value depends entirely on the placement of other pieces around them.

Soldiers move forward one tile at a time, but unlike international pawns, they can also move sideways from the start. They never go backward. There is no promotion. A soldier is a soldier all the way to the end of the board.

The horse and elephant are blockable. A horse is blocked if there is a piece directly adjacent to it in the direction of its move's first tile. An elephant is blocked similarly along its diagonal path. So pieces can be paralyzed by neighbors in a way they cannot in international chess.

This version is from 16Yongjin's MIT-licensed HTML5 collection. The implementation supports two local players taking turns on the same device. There is no AI in this version. The board is rendered in the traditional style with Korean characters on each piece for piece type identification.

Strategy in janggi shares features with international chess and adds new ones unique to the format. The cannon's leap-over rule means that pawn structure matters in a different way: you sometimes want to leave a friendly piece in a cannon's line of fire deliberately, because moving it would unblock the cannon for your own use. This creates positional tension that does not exist in international chess.

The general's confinement to the palace limits its mobility, but it also makes endgames more about coordinating the remaining pieces than about king safety. Once you have lost most of your major pieces, the game is largely decided. Janggi endgames tend to be shorter than international chess endgames because pieces cannot easily corner the general; the general is already cornered by the palace.

The opening principles are familiar: develop your major pieces, control the center, protect your home palace. The middlegame becomes a series of attacks and counter-attacks, often with cannons playing a central role because they can threaten multiple pieces from across the board.

A common beginner mistake is treating janggi like international chess. The two games share a heritage but the differences in piece movement and board geometry mean that good international chess players are not automatically good at janggi. Practice the cannon's logic specifically. A few games will rewire your intuition.

This implementation is best played as a casual learning tool rather than as a competitive match. The lack of AI means you need a partner to play against. The board view is clear and the piece movements are visualized when you hover over a piece. Most matches between casual players take twenty to forty minutes. Tournament-level games can run an hour or more. The version here keeps the rules clean and lets you focus on learning the format rather than fighting the interface.

Related: Tic-Tac-Toe, Drop Four, Five Stones