Scoring in riichi mahjong: the beginner’s guide

The five-step method

A hand’s value depends on two numbers: han, which measure what is remarkable about it, and fu, which measure its composition. You find them in this order:

1. Spot the yaku in the hand.
2. Add up their han, open or closed hand.
3. Add one han per dora, red five and ura-dora.
4. Count the fu, then round up to the ten.
5. Work out the points, or the limit reached, and what each player pays.

These are exactly the five steps of Tenpai’s training.

1. Yaku

A yaku is a recognised combination: no yaku, no win, even with four sets and a pair. There are about forty, but these cover most of a beginner’s hands:

• Riichi 1 han, closed only declaration Closed hand and riichi declared.
• Menzen tsumo 1 han, closed only closed-hand self-draw Win on your own draw with a closed hand (closed kans don’t open it).
• Tanyao 1 han all simples Only tiles from 2 to 8, no honours or terminals.
• Pinfu 1 han, closed only no-points hand Closed hand, four runs, a valueless pair and a ryanmen wait.
• Yakuhai: Chun 1 han red dragon Triplet or quad of red dragons.
• Iipeikou 1 han, closed only pure double run Two identical runs in the same suit, closed hand.
• Toitoi 2 han all triplets Four triplets or quads.
• Honitsu 3 han (2 open) half flush One suit plus honours.

All the others, with their open and closed value, are in the scoring sheet. See all the yaku.

2. Han

Each yaku is worth a number of han, and they add up: a hand with riichi, all simples and pinfu is worth 3 han. Some yaku are worth one han less when the hand is open (honitsu, chanta, ittsu…), others are only allowed in a closed hand.

Yakuman, like thirteen orphans, stand apart: they go straight to the maximum limit.

3. Dora

Once you have a yaku, each dora adds one han: the tile after the indicator, each red five, and with riichi, the ura-dora. A hand can go from 1 to 4 han thanks to its dora. How to read the dora indicator.

4. Fu

Fu fine-tune the value of hands under 5 han. You start from 20 fu, then add:

Runs are worth nothing. You then round up to the next ten: 32 fu become 40. Two fixed cases: seven pairs are always worth 25 fu, and a pinfu is worth 20 fu on tsumo, 30 on ron.

The waits

• Ryanmen (two-sided) : Ryanmen wait (either side of a run):
• Kanchan (middle) : Kanchan wait (middle tile of a run):
• Penchan (edge) : Penchan wait (3 for 1-2, or 7 for 8-9):
• Tanki (on the pair) : Tanki wait (on the pair):
• Shanpon (two pairs) : Shanpon wait (one of two pairs becomes a triplet), the triplet already carries its fu:

5. Points

Base points are fu × 2 to the power of (han + 2). A non-dealer who wins by ron gets 4 times this base; the dealer, 6 times. On tsumo, each non-dealer pays the base once and the dealer twice. Each payment is rounded up to the next hundred.

As soon as the base reaches 2,000, the hand is capped: that is mangan. Beyond that, only the han matter:

A hand scored from start to finish

You are South (non-dealer) during the East round. You declared riichi with this hand, which is waiting on the 6 of bamboo; the dora indicator is the 1 of characters. An opponent discards the 6: ron!

1. Yaku : Riichi (1 han) and Yakuhai: Chun (1 han).
2. Han : 2 han from yaku.
3. Dora : the 1 of characters indicator points to the 2: the hand has 1. Total, 3 han.
4. Fu :
   • Every regular hand starts at 20 fu (fuutei).
   • Ron with a closed hand (menzen kafu): +10 fu.
   • Closed triplet of terminals/honours: 8 fu.
   • Kanchan wait (middle tile of a run): 2 fu.
   Total: 40 fu.
5. Points : 40 × 2 to the power of 5 = 1,280 base points; × 4 for a non-dealer ron = 5,120, rounded up to 5,200.

Result: 3 han 40 fu, the player who discarded the 6 pays 5,200 points.

The values to know

At the table, nobody redoes the multiplication: you remember the most common amounts. Here is what a ron is worth, without kiriage mangan:

The full table, for every combination of han and fu, is in the scoring sheet. The most effective way is still to score hands: a few dozen are enough for the calculation to become a reflex. Score an easy hand.