Beginner's Lesson 17
Scoring System Basics
In this lesson, we will be covering the basics of the scoring system in riichi mahjong.
When scoring a hand, the first thing you have to do is add up the han that hand is worth. As explained in previous lessons, each yaku is worth a certain number of han from 1 to 6, and each dora in your hand is also worth 1 han. Hands worth 5 or more han are scored as “limit hands”. They are explained in the table below.
Number of han
*In some rulesets, any hand with 11 or more han is worth sanbaiman. In these rulesets, yakuman can only be scored by yakuman hands.
As you can see, limit hands all have point values that are multiples of 1000, which makes them easy to memorize. To provide some perspective, each player usually begins a game of riichi mahjong with 25000 or 30000 points.
And as an example, we will take a closer look at the cheapest limit hand, a mangan. A non-dealer mangan is always worth 8000 points. If you win a non-dealer mangan by ron, the player who dealt your winning tile has to pay the entire value of your hand: 8000 points. If you win a non-dealer mangan by tsumo, then the other 2 non-dealers each have to pay 2000 points and the dealer has to pay the remaining 4000 points. In scoring tables, that is written as “2000/4000”, with the smaller number being the value the non-dealers pay and the larger number being the value the dealer pays.
This asymmetry brings up some important aspects of the scoring system in riichi mahjong. A player who discards another player’s winning tile has to pay the full value of the hand. Not only can this cost you several points, but it also increases point gap between you and the other two players who were able to escape losing any points that hand. Because of these factors, defending against other players’ hands becomes an important skill. We will cover defense in a later lesson.
Also, the dealer has to pay twice as much as the non-dealers if one of the non-dealers wins by tsumo. However, any hand the dealer wins is worth 1.5 times what a non-dealer’s hand would be; a non-dealer mangan is 8000, but a dealer mangan is 12000. Because of this, if you win a dealer mangan by tsumo, each of the other 3 players have to pay 4000 points. In scoring tables, that is written as “4000 all”. These factors, as well as the possibility of dealer renchan, give the dealer more incentive to try and win their hand.
Moving on from the limit hands, hands worth 4 or less han take a little bit more effort to score. For these types of hands, you have to figure out how much “fu” the hand is worth. Fu is often translated as, “minipoints”, and depends on the final shape of the hand rather than the yaku. The only exception is chiitoitsu, which is always 25 fu.
Each hand is worth a minimum of 20 fu; this is the fu gained from simply winning the hand. From there, the hand may earn fu depending on how it was won. A closed hand won by ron gains 10 fu. A hand won by tsumo, regardless of if it was open or closed, gains 2 fu in most cases. These 2 fu from tsumo are waived if the hand qualifies for the pinfu yaku.
In fact, if the hand qualifies for pinfu, this is where the fu calculation stops. A pinfu hand won by ron is always 30 fu, and a pinfu hand won by tsumo is always 20 fu.
Continuing on, the final wait of the hand may be worth 2 fu. A penchan, kanchan, or tanki (single wait to complete the pair) wait are each worth 2 fu. A ryanmen and shanpon wait are not worth any fu. However, the triplet completed by the shanpon wait will be worth fu. That is because triplets and kans are worth varying degrees of fu. This is shown in the table below.
Terminal or Honor Tiles
Open triplet (minkou)
Closed triplet (ankou)
Open kan (minkan)
Closed kan (ankan)
As you can see, these are all multiples of 2. The lowest value is 2 for an open triplet of simple tiles. This value doubles if the set is closed or if it instead composed of terminal or honor tiles. The respective values quadruples if the set is upgraded to a kan.
The way in which a hand is won affects the value of the triplet completed by a shanpon wait. If the hand is won by ron, the triplet is treated as being open, but if the hand is won by tsumo, the triplet is treated as being closed. This concept was mentioned earlier with regards to the yaku san ankou and the yakuman suu ankou. You have to draw all three tiles yourself for a triplet to be considered an ankou.
The last thing to check for the fu calculation is the pair of the hand. If the pair would be considered yakuhai for that player, then it is worth 2 fu. Therefore, having a pair of haku, hatsu, chun, the round wind, or that player’s seat wind would be worth 2 fu. Additionally, if the pair would be that player’s double yakuhai (like the dealer’s pair of east in the east round), it is worth double: 4 fu.
The fact that yakuhai pairs are worth 2 fu is why having them disqualifies the hand for pinfu. That is also why pinfu has to be all sequences and have a ryanmen final wait, because sequences and ryanmen waits are not worth any fu. Having learned how to calculate fu, the strange conditions for pinfu suddenly make a lot of sense!
However, it is possible for an open hand to fulfill all of the conditions of pinfu, other than being closed. That would normally mean that it would be worth 20 fu, but in this special case, 2 fu are awarded for what is called “open pinfu”. Essentially, the only hand that can be worth 20 fu is a closed pinfu hand won by tsumo, so an “open pinfu” hand gains these special 2 fu.
In any case, once all of the fu of the hand is added up, it is rounded up to the nearest 10. That means that not every little bit of fu matters when scoring; a hand worth 32 fu and 40 fu will both be rounded to 40 fu when scoring. Once the fu is rounded up, it goes into the following formula, along with the han value of the hand.
base points = fu × 2^(2 + han)
You absolutely do NOT have to memorize this formula, but knowing it will make understanding the scoring system a little easier! Essentially, what this means is that the hand value doubles with each additional han, up to 4 han. Furthermore, a hand that is 4 or less han cannot be worth more than mangan; if it would exceed the value of a mangan (2000 base points), it is rounded down to mangan.
So what are these “base points”? They are the values from which the actual score of the hand is derived. The score of a hand is actually 4 or 6 times the base points, rounded up to the nearest 100. Again, you do not have to memorize that.
That is because, in practice, players use scoring tables to quickly score hands, without having to plug numbers into the formula above and perform the calculation. There are separate scoring tables for the dealer and non-dealers, just like the above example with the limit hands. We will cover these scoring tables over the next few lessons.
However, if you are interested in learning about the in-depth calculation, here is a video by Light Grunty explaining the scoring formula:
Scoring Formula and Scoring Tables
Basic Scoring Elements
Lastly, we will cover how the honba affect the score of a hand. In the previous lesson, we mentioned that each honba increased the value of the next hand by 300 points. The way that this occurs is simple: if a hand is won by tsumo, each player pays an additional 100 points per honba, and if a hand is won by ron, the player who dealt in pays an additional 300 points per honba. The value added by the honba is simply added to the numbers you pull from a scoring table.
For example, if a non-dealer wins a hand worth mangan by tsumo when there are 2 honba, then the other non-dealers would each pay 2200, and the dealer would pay 4200. If they instead won by ron, then the player who dealt their winning tile would pay 8600.
In the next lesson, we will cover the scoring table for the most common fu value: 30.