Mahjong Settlement Calculator - Uma & Oka
Automatically calculate settlement points and amounts reflecting Uma, Oka, and rates from base scores. Supports multiple rounds aggregation.
How to Use
- Select a rule preset (M-League, Free Mahjong House Standard, No Oka, or Sanma. You can also adjust starting points, return points, and Uma settings in Custom mode)
- Enter each player's base score (the last player's score can be auto-filled using the 'Auto-fill Remaining Player' button)
- Settlement points and breakdown reflecting rank, Uma, and Oka are displayed instantly (with zero-sum verification)
- When you select a rate like ten-go (×50) or ten-pin (×100), the monetary conversion is also displayed
- By adding to the session using 'Record This Round', you can aggregate total points and total amounts for multiple rounds
Use Cases
- When you want to quickly settle accounts for each round in casual mahjong games
- When explaining settlement with Uma and Oka to beginners with detailed breakdowns
- When you want to aggregate settlement for multiple rounds played in a day
- For Sanma (three-player mahjong) or custom rule settlements
Frequently Asked Questions
What is the difference between Uma and Oka? ▼
Uma are points exchanged based on ranking. For example, in One-Three (10-30), 1st place receives +30, 2nd place +10, 3rd place -10, and 4th place -30. Oka is a top bonus that comes from the difference between starting points and return points. For example, with starting points of 25000 and return points of 30000, (30000−25000)×4 players = 20000 points (20pt) is added to 1st place. This tool automatically calculates both and displays the breakdown.
How is 10-30 (One-Three) distributed? ▼
1st place +30pt, 2nd place +10pt, 3rd place -10pt, 4th place -30pt. '10-30' represents '10 points exchanged for 2nd and 3rd place, 30 points for 1st and 4th place'. Similarly, One-Two (10-20) is 1st place +20, 2nd place +10, 3rd place -10, 4th place -20.
How is ranking determined in case of a tie? ▼
This tool treats the player entered first as having a higher ranking. To match the common rule of 'players closer to the dealer having higher ranking', enter players in seating order. Splitting Uma and Oka for tied scores is not supported.
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