japanese mahjong calculator

How Japanese Mahjong Scoring Works

Japanese mahjong scoring can feel complicated at first because it combines han, fu, round-up rules, and several limit tiers like mangan and haneman. But once you break it into steps, it becomes very manageable.

This calculator follows standard riichi scoring logic used in many online clients and in-person rule sets. It helps you quickly estimate what the winner receives and what each payer owes.

Step 1: Find Basic Points

For regular hands (non-limit), the basic point value is:

Basic Points = fu × 2^(han + 2)

After this, the game converts basic points into actual payments depending on ron/tsumo and dealer status, then rounds up to the nearest 100.

Step 2: Check Limit Hands

If the hand reaches a limit, you do not use the regular fu formula. Instead, it uses fixed basic values:

• Mangan (typically 5 han, or high fu/han cap): basic 2000
• Haneman (6–7 han): basic 3000
• Baiman (8–10 han): basic 4000
• Sanbaiman (11–12 han): basic 6000
• Yakuman (13+ han counted yakuman, or explicit yakuman): basic 8000

Step 3: Convert to Payments

• Ron, non-dealer win: ceil(basic × 4)
• Ron, dealer win: ceil(basic × 6)
• Tsumo, non-dealer win: dealer pays ceil(basic × 2), each non-dealer pays ceil(basic × 1)
• Tsumo, dealer win: each non-dealer pays ceil(basic × 2)

All payments are rounded up to the nearest 100 points. Honba and riichi stick bonuses are then added on top.

Quick Limit Reference

Hand Tier	Han Range	Basic Points	Typical Non-Dealer Ron
Mangan	5 han (or capped)	2000	8000
Haneman	6–7 han	3000	12000
Baiman	8–10 han	4000	16000
Sanbaiman	11–12 han	6000	24000
Yakuman	13+ / Yakuman hand	8000	32000

How to Use the Calculator Efficiently

1) Enter han and fu

Start by entering the final han and fu of your winning hand. If your hand is a yakuman, set Yakuman Count instead (for example, 2 for double yakuman).

2) Set seat and win type

Dealer wins are paid at higher rates. Tsumo splits payments among opponents, while ron is paid by a single discarder.

3) Add table bonuses

Use honba for repeat counters and riichi sticks for sticks already on the table. These bonuses can significantly change final gain.

4) Use kiriage when your table allows it

Some rules promote 3 han 60 fu and 4 han 30 fu to mangan. Toggle kiriage if your local rules include it.

Common Scoring Mistakes

• Forgetting to round each payment up to the nearest 100
• Mixing up dealer and non-dealer payout formulas
• Adding honba incorrectly on tsumo (it is +100 per payer)
• Forgetting to include riichi sticks in winner total gain
• Treating capped hands as regular fu-based hands

Final Note

This tool is intended for fast practical calculation and study. Regional rules can differ (kiriage usage, counted yakuman handling, optional house rules), so always follow your table's official scoring policy when needed.