How Riichi Mahjong Scoring Works (Han, Fu, Tiers)
Riichi scoring looks intimidating but reduces to a small set of rules: count han, count fu, look up the base points, then apply ron / tsumo and dealer multipliers.
What is han?
Han (翻) is the number of doubles a hand earns. It is the sum of every yaku in the hand plus one han per dora you hold. A closed riichi + pinfu + tsumo + one dora is 1 + 1 + 1 + 1 = 4 han. Han drives the exponential growth of the score.
What is fu?
Fu (符) is the fine-grained base value that captures hand shape — 20 fu for the hand itself, plus extra fu for concealed triplets (4 per), kan, yakuhai pairs, the wait shape and the winning method. The total is rounded up to the next multiple of 10. A typical winning hand sits at 30 or 40 fu.
How are han and fu combined into points?
The base-point formula is fu × 2^(han + 2), but only the low-han hands (1-4 han below the mangan line) use it. From 5 han up, scoring switches to fixed tiers. So a 30-fu, 3-han hand has 30 × 2^5 = 960 base points, which is then multiplied for the payer role.
What are mangan / haneman / baiman / sanbaiman / yakuman?
These are fixed tiers used once the base formula stops being practical. Mangan (満貫) = 8000 base (5 han, or 4 han 40 fu+). Haneman (跳満) = 12000 (6-7 han). Baiman (倍満) = 16000 (8-10 han). Sanbaiman (三倍満) = 24000 (11-12 han). Yakuman (役満) = 32000 (13+ han or a yakuman hand). Dealer wins are 1.5× these numbers.
How is payment distributed?
On ron, the discarder pays the full amount alone. On tsumo, the three other players split it — non-dealers pay base, the dealer pays double. A non-dealer mangan tsumo (8000) splits as 4000 from the dealer and 2000 from each of the other two non-dealers. Dealer wins always pay (or earn) 1.5× the equivalent non-dealer amount.