Kan Rules in Mahjong: Ankan, Daiminkan, Shouminkan Explained
Kan declares a four-tile group, opens a fresh dora indicator and pulls a replacement tile from the dead wall. Here is how each of the three variants actually works.
What is a kan?
Kan (槓, "quad") is the declaration of a four-tile group made of identical tiles. In the four-melds-plus-pair structure, a kan replaces a triplet — it still counts as one meld, but it carries extra rules: a replacement draw from the dead wall, a fresh dora indicator that flips immediately, and (for the closed form) significant fu.
What are the three types of kan?
(1) Ankan (暗槓, closed kan) — declared from your hand only, on your own turn, after drawing. Hand stays closed. (2) Daiminkan (大明槓, open kan) — claim someone's discard to complete a kan using three identical tiles already in your hand. Opens the hand. (3) Shouminkan (小明槓, also called kakan) — add a fourth tile from your hand to an existing open pon. Hand stays open but does not become more open.
What is the rinshan tile?
Every kan declaration is immediately followed by a draw from the rinshan — the dead wall's replacement pile of four tiles. You discard normally after that draw. Winning ON the rinshan draw itself scores Rinshan Kaihou (1 han). The dead wall shrinks by one tile per kan, which is why most rulesets cap a single hand at four kans (or three, if all by one player).
How does kan affect dora?
Each kan flips a new dora indicator: a fresh top-of-stack tile in the dead wall is turned face up. This is the kan dora. Every player benefits, not just the kan-declarer. If the hand goes to a riichi win, an extra ura dora indicator under each kan dora is also flipped. So a 3-kan hand can produce 4 dora indicators plus 4 ura — sometimes massively shifting scores.
What is chankan?
Chankan (槍槓, "robbing a kan") is a special ron: when a player declares a shouminkan upgrade, any other player whose winning tile is exactly that fourth tile may ron on the upgrade instead of letting it complete. Ankan cannot normally be robbed except for kokushi (a thirteen-orphans waiting hand can chankan an ankan in many rulesets). Chankan itself is worth 1 han when triggered.