How to Calculate Riichi Mahjong Results | Uma, Oka, Conversion Rates, and Chips

Four values to distinguish when calculating results

To calculate results, determine these four values in order: the final point total, the base score, the final game points after placement adjustments, and the actual result expressed in P. The difference between the final point total and return points, expressed in units of 1,000 points, is called the base score (soten). Points added or subtracted according to placement are called placement points (jun’iten) and are treated as uma in this article’s examples. P is the unit used in this article’s calculation examples.

In four-player mahjong with 25,000 starting points and a 30,000-point return, the 5,000-point difference per player across four players leaves the base-score total 20 points short. The oka is the first-place bonus that makes up this shortfall. In this example, +20 is added to first place.

Distinguish between point sticks, final game points, and P

The 40,000 points held at the table, the final game-points value of +50 written on the settlement sheet, and the converted +5,000P are different values. Recording the unit prevents mistakes such as dividing +50 by 1,000 again or adding uma directly to 40,000.

points

Point sticks on the table. They move after each hand due to wins, deal-ins, and draws.

Base score

An intermediate settlement value, usually expressed in units of 1,000 points, representing the difference between the final point total and return points.

Final game points

The value after placement settlement, with uma, oka, and other adjustments applied to the base score.

P

The conversion unit used in this article’s calculation examples.

Oka is not “a sudden 20-point bonus for first place”

In four-player mahjong starting at 25,000 points with a 30,000-point return, the starting total is 100,000 points, while the return-point baseline totals 120,000 points. The base scores therefore total −20 points. Returning those 20 points to first place makes the combined base scores and oka total 0.

This difference does not arise when the starting points and return points are the same. Some tables do not use oka, so do not rely on the name alone; confirm the starting points, return points, and points awarded to first place.

Calculate the four values in five steps

1. Finalize each player’s point total: At this stage, apply the table rules for tied placements and handling remainders in the hundreds.
2. Calculate the base score: The standard formula is “(final point total − return points) ÷ 1,000.” This converts point-stick totals into settlement points.
3. Apply uma and oka: Add or subtract placement points, then add oka to first place. These adjustments determine the final game points.
4. Apply the rate and chips: Multiply the final game points by the rate, then add or subtract the number of chips × chip value.
5. Deduct the table fee: Follow the agreed shares for each player’s portion of the total table fee.

If you already record a value including oka and uma as the final game points, do not add them again. Clearly specify whether each input is a final point total, base score, final game points, or actual net result.

First, state the game rules in one line

Before calculating, write the conditions in one line, such as “four-player mahjong, 25,000 starting points with a 30,000-point return, 10-20 uma, 20 oka, and fractions handled according to the table rules.” “10-20” generally means +20 for 1st, +10 for 2nd, −10 for 3rd, and −20 for 4th, but the shorthand alone can be misunderstood. List the allocation for all four placements in the settlement table.

Competitive organizations and online mahjong platforms do not all use the same starting points, return points, placement bonuses, or fraction-handling rules. For example, M.LEAGUE defines its own starting points and placement bonuses, while Saikouisen uses different provisions depending on the competition rules. Do not treat the figures in this guide as the sole standard; prioritize the settings used for your game.

Four-player mahjong net result example

From final point totals to final game points

Assume final point totals of 40,000, 30,000, 20,000, and 10,000 points. Calculate each base score from the difference against the return points, then apply uma and oka to determine the final game points.

Convert to P to calculate the actual net result

Chip counts are +5 for 1st place, −1 for 2nd, −2 for 3rd, and −2 for 4th. The table fee is 400P per player.

Calculating 1st place step by step

1. Base score: (40,000 points − 30,000 points) ÷ 1,000 = +10 points
2. Uma and oka:+10 + 20 + 20 = +50 points
3. Point conversion: +50 × 100P = +5,000P
4. Chips:+5 chips × 100P = +500P
5. Table fee: +5,000P + 500P − 400P = +5,100P

Reading across each row, 1st place goes from 40,000 points to +10, +50, and +5,100P. 2nd place goes from 30,000 points to 0, +10, and +500P. 3rd place goes from 20,000 points to −10, −20, and −2,600P, while 4th place goes from 10,000 points to −20, −40, and −4,600P. In a spreadsheet, putting the base score, placement bonus, conversion, chips, and table fee in separate columns lets you identify where a discrepancy arose.

Why oka and uma are zero-sum

The base scores in this example are +10, 0, −10, and −20, totaling −20. Adding the winner’s +20 oka brings the total to 0, while the uma of +20, +10, −10, and −20 also total 0. Chips likewise total 0 because every chip received corresponds to one paid. Only the table fee is treated separately because it leaves the table.

Check final game points and actual profit/loss separately

The final game points total 0

In this example, the final game points of +50, +10, −20, and −40 add up to 0. The adopted uma and oka cover the shortfall in the base scores, so settlement consists entirely of transfers within the table. The chips also total 0 at +5, −1, −2, and −2, so the total profit/loss before deducting the table fee is 0P.

The total actual profit/loss is negative only by the table fee

After applying the table fee, the final results are +5,100P, +500P, −2,600P, and −4,600P, totaling −1,600P. This matches the total table fee of 1,600P in absolute value, confirming that the calculation is correct.

Decide rounding, ties, and bust bonuses before calculating

After understanding the basic example, account for differences between tables. If the final point total is 35,700 points, the difference from a 30,000-point return is +5,700 points, making the base score +5.7 points. The adopted rules determine whether to keep +5.7 or round it to an integer, and whether to round up, down, or to the nearest integer.

Apply the same rounding rule to every player

If rounding is used, apply it only once, immediately after entering the final point totals. Rounding the base score and then rounding the same fraction again when converting to P compounds the error. If the rules do not produce a total of 0 after rounding, they may specify an additional step, such as assigning the remainder to the winner. Do not make a convenient adjustment for just one player; record the method agreed on before the game.

Ties: determine placement before applying uma

When players finish with the same point total, the rules may rank the player closest to the starting dealer higher or split the placement points. Since different placements receive different uma even with the same final point total, determine placement first, then add the placement points. Record both the final point total and confirmed placement.

Use separate columns for bonuses such as bust bonuses and yakitori

When using additional bonuses, specify how many points move from whom to whom rather than combining them in a single field such as “Other adjustments,” which makes verification easier. For example, if a bust bonus transfers 5 points from one player to another, enter +5 for the recipient and −5 for the payer at the same time. If the rules treat it as a bonus added from an external source, it will not be zero-sum, so note the reason and source.

Decide who receives the riichi sticks left on the table

Point sticks wagered with riichi declarations and left on the table when the game ends are kyotaku. Rules differ on who receives the remaining kyotaku at the end or whether they carry over to the next game. Also record when they are applied to avoid counting them in both the final point total and final game points.

Common settlement calculation mistakes

Treating the final point total and final game points as the same unit

A final point total of 40,000 and a final game-points value of +50 are different values. Subtract the return points from the final point total, express the difference in units of 1,000 points, then apply uma and oka.

Confusing starting points with return points

With 25,000 starting points and a 30,000-point return, players begin the game with 25,000 points, while 30,000 points is the return-point baseline used to calculate the base score. The difference funds the oka.

Mixing table fees into game results

The table fee is the cost of using the table. Recording it separately from gains and losses from play lets you check both your pure results and actual expenses.

Compare games played under different rules as-is

If the uma, oka, rate, chips, or table fee differ, the same placement can produce different earnings. For long-term totals, separate three-player and four-player mahjong at a minimum, and record the main rules as well.

Treat the oka as “points distributed to everyone”

In this example, the +20 oka is awarded to the winner to offset the −20 total base score caused by the difference from the return points. It is neither +20 distributed to each of the 4 players nor a value added twice, separately from the winner’s base score. Calculate the total oka once from the starting and return points, then confirm the recipient.

Adding chips to the final point total or final game points

Because chips are exchanged outside the point-stick total, do not turn 40,000 points into 40,500 points or a final game-points value of +50 into +55. After converting the final game points into P, add or subtract chips × value per chip in a separate column. This lets you produce results excluding chips from the same game records.

Compare values including table fees as “mahjong results”

If the table fee is always the same, the total including table fees falls as the number of games increases. To assess pure game results, calculate “earnings through points and chips” separately from “final earnings including table fees.” The two figures decline for different reasons, so combining them in one graph can lead to misreading your results.

Ready-to-use results calculation sheet

Whether you use paper, a spreadsheet, or an app, creating columns in the following order makes recalculation possible. Keep input and calculated fields separate, and do not overwrite the applied rules midway.

Troubleshooting calculation discrepancies

Check the calculations at four stages (B, F, H, and J), not just at the end. Finding a discrepancy early avoids having to redo all subsequent multiplications.

Items to record with the balance

• Game date, time, and players
• Game format, such as three-player or four-player and east-only or hanchan
• Starting points, return points, uma, and oka
• Handling point remainders below 1,000 and placement ties
• Additional rules, such as bust bonuses
• Rate, chip value, and number of chips
• Total table fees and how they are split
• Final point total, base score, final game points, and final net result

In three-player mahjong, the placement-point distribution and starting points can vary greatly. For details, see How to Record Uma and Net Results in Three-Player Mahjong.

Use consistent rules when aggregating results

You can combine results from different rules if you only need the total net result, but this is unsuitable for analyzing causes. Even the same +50 points means something different under four-player uma of 10-20 than under another placement-point system. Record enough detail to filter by three-player or four-player, east-only or east-south, starting points, return points, uma, and whether chips are used. This lets you investigate changes separately, such as “My placements improved, but my net result after table fees declined.”

Average placement, first-place rate, and last-place rate are placement metrics unaffected by rates or table fees. When comparing them with net results, use games from the same period under the same rules. For details on interpreting these metrics, see What Is a Good Average Placement in Mahjong?.

Summary

Calculate mahjong net results in this order: final point total, base score, final game points including uma and oka, and the net result converted into P. Checking final game points separately from net results after table fees shows where any discrepancy occurred.