Simples
By Kenji Tanaka · Updated
Definition
Simples (chunchanhai) are the 2 through 8 of each suit, the middle tiles. They extend runs in both directions, which makes them the most flexible tiles in the game and the entire basis of tanyao. The same flexibility is why they are the most dangerous discards against a tenpai opponent: middle tiles complete the most waits, terminals and honors the fewest.
Simples
Simples are the numbered tiles 2 through 8 in each of the three suited tile categories (bamboo, character, and dot suits). They form the middle range of suited tiles, excluding both the terminal tiles (1 and 9) and all honor tiles (winds and dragons). Simples are fundamental to several important mahjong yaku, most notably tanyao.
Understanding Simples
In mahjong, each suited tile category contains nine numbered tiles, ranked 1 through 9. The simples occupy the middle positions of this sequence, making them the most abundant tile category in standard play. There are 28 simples in each suit (four copies each of 2, 3, 4, 5, 6, 7, and 8), for a total of 84 simple tiles in the complete 136-tile set.
The distinction between simples, terminals, and honors is crucial for understanding many yaku. While terminals (1s and 9s) are considered “outside” tiles with limited flexibility in forming sequences, simples are the most versatile tiles for constructing melds. They can form sequences (shuntsu) easily with adjacent numbered tiles, and they appear frequently enough to support various winning patterns.
The term “simples” comes from the concept that these tiles are “simple” or ordinary, they lack the special status of terminals or honors. This classification has significant strategic implications in hand composition and yaku selection.
Usage in Yaku
Simples are essential components of several yaku:
Tanyao (All Simples): This yaku requires the entire winning hand to consist exclusively of simples. No terminals or honors can appear in any melds or the pair. Tanyao is worth 1 han whether closed or open (open tanyao requires the kuitan rule), making it one of the most commonly achieved yaku.
Junchan (Pure Terminals): This yaku requires the opposite composition, every meld and the pair must contain a terminal (1 or 9), with no honor tiles anywhere. The related yaku chanta allows honors as well. Junchan cannot contain any pure simple sequences, making it substantially more difficult than tanyao.
Kuitan: This is not a yaku itself but rather a rule variation that determines whether open tanyao is permitted. When kuitan is allowed, players may declare tanyao with an open hand (containing at least one called meld), making simple-based hands more accessible.
Practical Example
Consider a winning hand with the following composition:
Melds: 2-3-4 bamboo, 5-6-7 character, 5-6-7 dot, 2-2-2 bamboo Pair: 3-3 dot
This hand contains only simples from each suit and would qualify for tanyao. If this hand were closed (all tiles drawn), it would score 1 han for tanyao (plus points from other elements). If it were open with called melds, tanyao would only score if kuitan is in effect.
In contrast, if the hand included even a single 1 or 9 tile, or any honor tile, tanyao would no longer be valid.
Related Terms
Tanyao
断么九
All simples: a hand built entirely from the number tiles 2 through 8, with no terminals and no honors. Worth 1 han. Most modern rule sets keep it valid when the hand is opened (the kuitan rule), which makes tanyao the workhorse yaku of fast open hands.
Terminal
么九牌
Terminals are the 1s and 9s, the tiles at the ends of each suit. They extend sequences in only one direction, which makes them less flexible than middle tiles but also safer to discard on defense, since fewer waits catch them. Several hands are built on them: chanta and junchan demand a terminal or honor in every block, and the yakuman chinroutou uses terminals alone. Grouped with the honors they form the yaochuuhai family.