Riichi Mahjong · Closed 1 / open 1

Yakuhai (Value Tiles) in Riichi Mahjong: Dragons, Seat and Round Winds, Double Wind

In riichi mahjong, Yakuhai (value tiles) is worth 1 han: a triplet (three of a kind) or quad of a dragon (white, green, red), your own seat wind, or the round wind. Calling it keeps it at 1 han, which makes yakuhai the standard way to "lock in a yaku" before you start calling tiles.

The kinds of yakuhai

Each triplet counts separately: triplets of white and red dragon are two yakuhai. A wind only counts if it is your seat wind or the round wind; as South in the East round, a triplet of West or North is worth nothing (it isn't a yaku).

Double wind: double East, double South

When your seat wind is also the round wind, that triplet scores both seat wind and round wind — two yakuhai, 2 han. The dealer's East in the East round (double East) and South's South in the South round (double South) are the familiar ones.

A pair is not a yaku

Yakuhai needs a triplet or quad. A pair of dragons, seat wind or round wind gives no han, just a little fu:

• A pair of a dragon, the seat wind or the round wind is 2 fu each; a double-wind pair is 4 fu here (same as Mahjong Soul and Tenhou; some tournament rules give 2)
• With a value pair, there's no pinfu: see Pinfu

How yakuhai is scored

The yaku, han, fu and points below are computed live by the same scoring code the game uses.

Common combinations:

The fastest open yaku: atozuke and one-sided waits

Yakuhai's strength is that a pon gives you a yaku. An open hand with no yaku can't win, so a pair of value tiles is your insurance.

• Atozuke (yaku added last): you may call other tiles first and only pon (or draw into) the value triplet at the end; it still wins here. The scorer only checks whether the finished hand has a yaku, with no "yaku first" rule (same as Mahjong Soul and Tenhou).
• One-sided wins: on a shanpon wait between a value tile and another tile, only the value tile gives a yaku. In the hand below, with no other yaku, white dragon wins and 9 bamboo has no yaku and can't win (the game won't show a win button).

• Keep or let go: keep a value pair while you can still pon it; once one copy has been discarded, only one is left and the chance to call is small, so it's usually time to cut it.

How it relates to other yaku

• Shousangen, Daisangen: two dragon triplets plus a dragon pair is shousangen; all three dragon triplets is the daisangen yakuman.
• Shousuushii, Daisuushii: three or four wind triplets, both yakuman; the seat and round winds inside them aren't counted again, since yakuman don't add up with normal yaku.
• Honitsu, Toitoi: honors can only be called by pon, so a hand with several value tiles drifts toward these two.
• Tsuuiisou: the all-honors yakuman.

Yakuhai odds

Do you start with a value pair?

You need a pair before you can pon. In a 13-tile starting hand, at least one dragon is a pair or better about 13% of the time, and two or more dragons about 0.46%. Seat-wind and round-wind pairs come on top of that.

Source: 1,000,000 random 13-tile deals.

How often it shows up in play

Four normal-level computers played 40,000 hands on this site's table, with 33,226 wins:

• 40% of wins had yakuhai (any of the five) — second only to riichi — and 96% of those were open hands.
• White dragon alone appears in 9.2%.
• Wins with yakuhai averaged 3,500 points, against 5,500 for all wins: yakuhai hands are often just 1 or 2 han and earn through speed.

Source: 40,000 computer hands on this site (all four at normal level), 33,226 wins. A win usually has several yaku, so the shares add up to more than 100%.

Yakuhai in other mahjong styles

Dragon and wind triplets score in every style, but differently:

• Taiwanese mahjong: dragon triplets, prevailing wind and seat wind are 1 tai each (Taiwanese mahjong tai list)
• Hong Kong mahjong: dragon, prevailing wind and seat wind triplets are 1 fan each (Hong Kong mahjong fan table)
• Chinese Official (Guobiao): dragon pung, prevalent wind and seat wind are 2 fan each (Guobiao fan list)
• Sichuan mahjong has no honor tiles, so nothing like it

FAQ

How many han is yakuhai?

1 han per triplet, and still 1 han when called. When the seat wind is also the round wind (double East, double South), one triplet is 2 han.

Does a pair of value tiles count as yakuhai?

No. Yakuhai needs a triplet or quad; a pair only adds 2 fu (4 for a double wind) and rules out pinfu.

Can I call other tiles first and pon the value tile last?

Yes. Like Mahjong Soul and Tenhou, this game allows atozuke: all that matters is having a yaku when you win.

Is North a yakuhai?

In four-player games, only for the North seat as its seat wind (round winds go up to West). The three-player game here has no North seat, so North is never a seat or round wind and a North triplet isn't a yaku; North is usually set aside as nukidora.

Related yaku

Shousangen Closed 2 / open 2 Two dragon triplets and a dragon pair: 2 han, at least 4 with its two yakuhai. Honitsu Closed 3 / open 2 One suit plus honors — 3 han closed, 2 open. Examples, honitsu vs chinitsu, and how many tiles you need to go for it. Toitoi Closed 2 / open 2 Four triplets and a pair, still 2 han when open. Examples, scoring combos and how many starting pairs you need.