What is Tanyao? All Simples in Riichi Mahjong Explained
Tanyao is the gateway yaku for open hands — easy to spot, easy to score, and combines with most others. Here is the rule and when it shines.
What is tanyao?
Tanyao (断幺九, literally "cut off the terminals") is a 1-han yaku scored by completing a hand that contains no terminal tiles (1s and 9s of suits) and no honor tiles. Only the 2-8 of manzu, pinzu and souzu are allowed. A pinfu of all simples is the textbook example.
Which tiles are terminals and honors?
Terminals are the 1s and 9s of each numbered suit — six tile types in total (1m, 9m, 1p, 9p, 1s, 9s). Honors are the four winds (East / South / West / North) and the three dragons (White / Green / Red) — seven more tile types. Tanyao excludes all thirteen of them.
Can I score tanyao on an open hand (kuitan)?
Modern rulesets — online clients and most casual or tournament tables — allow open tanyao (kuitan / 喰い断). Strict traditional rules forbid it: you would need the hand to stay closed. Agree on the ruleset before the first hand. Under kuitan-on rules, tanyao is the most popular open-hand yaku because it stays at 1 han whether closed or open.
What yaku stack with tanyao?
Tanyao layers freely with pinfu, iipeiko, sanshoku, ittsu, toitoi, sanankou, ryanpeikou and chinitsu — anything whose shape does not require terminals or honors. It is incompatible with yakuhai (needs honor triplets), chanta / junchan (require a terminal or honor in every meld) and honroutou (entirely terminals and honors).
When should I aim for tanyao?
Tanyao is the right target when your starting hand is heavy on middle tiles (3-7 of any suit) and light on terminals and honors. Discarding the terminal-and-honor tiles you pick up early commits to the shape without spending shanten. It pairs particularly well with riichi (closed) or with one quick pon to lock the yaku open.
Train the pattern
Look at each hand and decide before revealing the answer.
234m 567m 345p 678s 55s
Reveal answer
Every tile is 2-8 of a numbered suit. No terminals, no honors. Tanyao scores whether the hand is open or closed (under kuitan rules).
123m 567m 345p 678s 55s
Reveal answer
The 1 in 123m is a terminal. Tanyao excludes every 1 and 9 across the three numbered suits, so a single 1m kills the yaku.
234m 567m 345p 678s 55z
Reveal answer
5z is haku (white dragon), an honor tile. Tanyao excludes all winds and dragons. Note this hand cannot score yakuhai either — yakuhai needs a triplet of honors, not a pair.