Curriculum · 17 / 50
Chanta, junchan, and chiitoitsu
Chanta is 2 han with a terminal or honor in every group, junchan 3 han with no honors at all, and chiitoitsu 2 han for seven different pairs.
The principle
Chanta (混全帯幺九) requires every group and the pair to contain at least one terminal (1 or 9) or honor tile (a wind or dragon). The hand must also include at least one sequence and at least one honor. It is worth 2 han closed, and kuisagari drops it to 1 han once the hand is open.
Rule and example
Junchan (純全帯幺九) is the pure form of chanta: every group and the pair still touches a terminal, but no honor tiles are allowed. That stricter demand pays better, at 3 han closed and 2 han open. Because it bans honors, you never score chanta and junchan together: junchan takes precedence.
What changes
Chiitoitsu (七対子) breaks from the usual four-groups-and-a-pair structure: it is seven pairs, all different. The yaku is worth 2 han and is always closed, since you cannot call pairs. Its fu is fixed at 25, which makes its scores very consistent.
Mistake to avoid
Watch the chiitoitsu trap: the seven pairs must be distinct, and four identical tiles never count as two pairs. Chiitoitsu cannot combine with chanta or junchan because both require at least one run. It can instead combine with honitsu or chinitsu. A closed chanta or junchan hand can also include iipeikou when it contains two identical runs.
Rules references
- Tenhou rulesReference profile used for game mechanics and scoring.
- WRC Rules 2025International rules compared whenever their options differ from Tenhou.