Japanese mahjong

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Japanese mahjong 「麻雀、 麻将、 or マージャン」, or riichi mahjong, is the Japanese variation to the 4-player table game of mahjong. Best described as a combination of gin rummy and poker, it is a game that combines the elements of calculation and strategy with elements of risk assessment, observation skills, and luck. It is traditionally played with tiles.

The Japanese variation is primarily played in Japan, though it is available worldwide through internet sites and video games. Throughout the past 15 years, the game has gained increased prominence in western cultures through mahjong-centric media.


Mahjong as a whole is only a roughly 100 year old game. Originating in China, the game managed to spread across the country, East Asia, and even to the United States during the 1920s. The riichi variant only started emerging in Japan after World War 2. The modern riichi variant played today began in the 1960's, while the addition of red 5's started appearing in the 1980's. Mahjong started out as a gambling game, though playing for fun or sport is also common.

Basic Overview

The object of riichi mahjong is to score the most points. At the start of each round, players draw and discard tiles, competing to be the first to get a winning hand. When a player wins, the hand is scored based on its value. If the hand is won directly off another player's discard, the discarder must pay the winning player for its value. If a player draws their own winning tile, everyone else splits the payment. After a player wins, hands reset, and the next round starts. Once the final round ends, the game ends, and whoever has the most points wins first place.

There are two requirements to win a hand:

  • A hand needs a "winning shape". With a few exceptions, players must make a hand with that contains tile groups (either sequences, 1-2-3; or triplets, 3-3-3) and one pair (3-3). This is similar to how gin rummy is played. In mahjong, you need 4 tile groups + 1 pair to win.
  • A hand must have at least one yaku. Yaku can be compared to "poker hands" - they are patterns/criteria that score points. For example, a "pair" in poker means having two of the same number. Toitoi ("All Triplets") is when the hand consists entirely of triplets (that is, having 4 triplets in total). In general, yaku that that are harder to get scores more han, which translates to more points.

Mahjong is a zero-sum game - whenever a player gains points, the other players lose a total of that many points. Therefore, developing hands quickly and minimizing point losses are important aspects to the games. Sometimes, it is best to give up winning in order to prevent paying for others' hands.

The rules to the game are complex. Japanese mahjong's gameplay is generally similar to most Asia-originated variants of mahjong. For a more detailed overview, see the rules overview page, or the rest of this article.


The game of mahjong has numerous variations across the world, including an attempted standardization of "World Mahjong". Virtually every country in East Asia and the United States has a form of mahjong. While they all have the same general principles, they each have very distinct rule variations.

Japanese mahjong sets itself apart with a few key mechanics:

Mahjong tiles and suits

Standard Japanese mahjong tiles

There are 34 unique tile types in riichi mahjong, and 4 copies of each tile, for a total of 136 tiles. They can be split into two categories:

Number tiles (suits): there are three different suits of number tiles. Each number suit has tiles from 1 thru 9. Number tiles can be used to create sequences and triplets.

  • Manzu (characters) - Manzu are labeled on the top with Chinese characters from 1-9.
  • Pinzu (dots/circles) - Look like coins/circles. The amount of circles is the number of the tile.
  • Souzu (bamboos) - The face of the one of bamboo has a bird design on it. Other copies of the suit are numbered by the amount of sticks.

Of special interest are the terminal tiles - these are the 1 and 9 tiles of each suit. Sequences cannot "wrap around" from 9 -> 1 (i.e. you can't have an 891 sequence), so these tiles are harder to use. Terminals are subject to a few special yaku. Numbers from 2-8 are known as simples.

Jihai (honor tiles/word tiles): these can be further split into two categories. Honor tiles cannot be used to create sequences, only triplets.

  • Kazehai (wind tiles) - labeled in the four cardinal directions: Ton (east), Nan (north), Xia (west), Pei (north).
  • Sangenpai (dragon tiles) - White, Green, and Red.

Modern Japanese mahjong sets also come with four red five dora tiles. One number five character tile, two number five circle tiles, and one number five bamboo tile are replaced with their matching red tiles. These red dora tiles can replace the appropriate number of standard five-tiles. Using the red dora tiles is optional.

Many mahjong sets also come with flower and season tiles, but these are not used in riichi mahjong.

Game setup

When playing with physical tiles, setup is required. Online mahjong sites will set the game up for you, while the process can be made easier with an automatic table.

To set up the game, first, shuffle the tiles. Then, stack four walls that are 17 tiles long and 2 tiles high. Each player is responsible for their own wall. A dice roll is used to determine the initial dealer, as well as the wall break at the beginning of the hand. From where the wall breaks, deal each player 13 tiles to produce their starting hands, and separate the dead wall. Play begins once the dealer makes the initial draw and discard.



After the initial setup, the game may begin. The dealer (East) begins their first turn, then play proceeds counter-clockwise (to the right). The play order is East -> South -> West -> North.

A rough outline of each turn is as follows:

  • Draw one tile.
  • If the drawn tile is a tile that completes a valid winning hand, you may win.
  • You may declare riichi and/or kan if eligible. (More on these later)
  • Discard one tile.
  • Opponents may be able to claim your discarded tile. If the tile is not claimed, the next player begins their turn as normal.
    • Opponents can win off your discarded tile (ron) if they have a valid hand. They may also call chii, pon, or kan to take the tile and advance their hand.

This continues until the hand ends.

Discard pile

Every player's discard is organized and arranged in front of them. By convention, players line up their discarded tiles in rows of six. This exact arrangement is not necessary per-se, but it is preferred. The arranged discard pile is used for two primary purposes: as record of a player's discards, and as an indicator of safe-tiles for defensive play. Additionally, players can learn and are able to discern player hand states by reading the discard piles.

Hand development

As players draw and discard tiles, they "develop" their hand, getting closer and closer to winning.

Tile groups

Usually, a winning hand is a hand that contains 4 groups (either sequences or triplets) and 1 pair.

  • Sequences: Sequences are 3 consecutive number tiles of the same suit. Sequences may not "wrap around" from 9 to 1, so sequences of 891 or 912 are not allowed. Honor tiles cannot be used in sequences.
Closed Open
  • Triplets: Triplets are three identical tiles. Any type of tile may be used in a triplet.
Closed Open
  • Quads: Quads are a special form of triplet. They are four identical tiles. Even though a quad is four tiles, it is treated as a triplet with one extra tile. Therefore, when making a quad, one extra tile is drawn to keep "four groups + 1 pair".
    • In order to form a quad, you must call kan. Four of the same tile in your hand is not a group. You can only declare kan if you have 4 of the same tile, or have 3 of the same tile and a fourth is discarded.
    • When forming a quad, there are a few special procedures. First, call "kan" during your turn. Then, reveal the quadruplet and set it aside. Then, draw one tile from the dead wall into your hand. You must also reveal a kandora (see dora for more info on this). Finally, you discard like normal (or call kan again).
    • Because calling kan reveals kandora, quads are risky to form. While the kandora may benefit you, it also benefits all of your opponents.
  • Pairs: Pairs are two identical tiles. Any type of tile may be used.

Winning hands

As mentioned above, most winning hands are composed of four groups and one pair. If no quads are formed, this is 14 tiles in total. In addition, all winning hands must have at least one yaku.

Wining Hand example:

- 2 sequences () + ), 2 triplets ( () + ), 1 pair (

A winning hand is 14 tiles. However, in mahjong, you can only hold 13 tiles in your hand. Therefore, players must get to tenpai (ready hand) - a hand that is one tile away from winning - first. Once reaching tenpai, you can win the hand by either drawing a winning tile, or winning from an opponent's discard. With a normal hand structure, there are two ways to get to tenpai:

Tenpai #1 - 3 complete groups + 1 incomplete group + 1 pair:

- May win off: or to complete a sequence.

Tenpai #2 - 4 complete groups + 1 tile waiting to be paired

- May win off: to complete the pair. (This type of tenpai is generally rarer than tenpai #1)

A hand that is one tile away from being complete is in tenpai. A hand that is one away from tenpai (two from winning) is 1-shanten. A hand that is two away from tenpai (three from winning) is 2-shanten, and so on. A hand with a high shanten count is far away from winning, and may be too slow to be worth winning. When you are making a hand, you should focus on making incomplete groups and completing them.

There are two exceptions to the 4 tile groups and a pair pattern: Seven Pairs and Thirteen Orphans.

Claiming discards

As part of the game, players have the ability to claim other player's discards through chii, pon, and kan.

  • Chii: Call to complete a sequence. Chii can only be done to discards from the player directly before you in turn order (the player left of you).
  • Pon: Call to complete a triplet. Pon may be done on any player's discards. Pon may cause a player's turn to be skipped.
  • Kan: Call to complete a quad. See the kan page for the procedure. Not all kans are claimed from another player's discard.

When you have claimed an opponent's discard, your hand becomes open. When the hand is opened, some yaku are impossible to get, and other yaku are reduced in value. Open hands can complete faster, and some yaku do not reduce in value when opened. Any hand that is not open is considered closed. A key part of the game's strategy is deciding if you want to open the hand.


When the hand is closed and the hand is tenpai, you may declare riichi.

  • Cons: Riichi declares that you are about to win, and you are required to bet 1000 points. The 1000-point bet goes to whoever wins next (which may or may not be you). Also, you are not allowed to change your hand anymore. Therefore, you may end up dealing into other players, if you don't win first.
  • Pros: Riichi is a yaku, allowing otherwise yakuless hands to win. It is always worth at least one han, and gives the chance for even more han, which both can greatly increase the value of the hand.
Being the first declare riichi is especially powerful. Since only one player can win the hand, being first to tenpai gives a speed advantage. Plus, other players do not know the value of your hand, so even if your hand is cheap, declaring riichi can scare off opponents. It is best not to rely on scare tactics, but it is a consideration.

Riichi is a major part of the game's strategy. It is the single most common yaku. Even if you do not know any other yaku, you can always use riichi if you have a closed hand. However, it is not always a good idea to declare riichi. In addition, you should watch out when other players call riichi.


Example discard pile

2-pin in this discard applies furiten to the example hand

Furiten is a rule that may prevent a player from winning off other's discards.

When any of the tiles you've discarded could've completed a winning hand, you become completely unable to win off of another player's discard. In other words, you cannot win by ron. However, while in furiten, it is still possible to win by drawing the tile yourself.

Note that it does not matter if the tile you discarded and the tile the opponent discarded are different, when you are in furiten, all tile types are affected. It does not matter if you couldn't actually win off the tile because you did not have a yaku, if the discarded tile could complete the "winning shape", it is furiten.

For example, say a player's hand looks like this:

  • Example tenpai hand:
Waiting for: - , or

This example hand is a tenpai hand waiting three tiles. If any of those tiles are in the player's discard pile, then the player cannot claim ron. A player can get out of furiten by changing the hand composition.

This rule forces players to take extra consideration when making discards. Often, a player must have good reason to discard particular tiles, especially when they are already part of a tile group.

End of a hand

The procedure of drawing, discarding, and maintaining a round ends with a few different scenarios. A player can win the hand, the tiles can run out, or a few "abortive draws" force the game to be restarted. Afterwards, the tiles are reshuffled to setup the next hand, or renchan.

Winning a hand

Ideally, players seek to win hands. Once again, a winning hand is a tenpai hand that gains its winning tile. A player must actively declare the win (ron or tsumo). In a few niche cases, you may want to decline winning (e.g. when you'd bankrupt a player).

It is most important to note: winning a hand requires a minimum of one yaku. Failure to meet this requirement may be subject to a penalty.

Depending on the rules, multiple player may win from a hand. This occurs when more than one player is waiting on the same tile, and that tile is discarded. This event is called a double ron or even triple ron. Some rules allow double ron but not triple ron. Some rules allow triple ron. Other rulesets apply the head bump rule (atamahane) - only one player wins the hand. When atamahane is used, the player closest in turn order to the next player claims the win.

Exhaustive draw

Ryuukyoku, or exhaustive draw, occurs when all the tiles (except the dead wall) run out. The player(s) in tenpai receive points from those in noten, but do not win the hand. Nearly 40% of professional games go to an exhaustive draw, as players often stop trying to win once another player declares riichi.

Abortive draw

Various conditions may allow players to abort the hand. In other words, a mahjong hand may end prematurely before anyone claims a win or before all the tiles are drawn and discarded. In these events, no points are exchanged; and no penalties are enforced. Instead, the hand ends, and the tiles are reshuffled.


A chombo is a penalty for an illegal procedure. Chombo are often awarded when a player does something that would prevent the game from continuing normally, e.g. knocking off an entire wall of tiles. In these cases, the hand restarts. Chombo may also be awarded after a hand ends, e.g. for an illegal riichi.

In the event of chombo, the player must pay out a penalty of points, usually mangan. In casual settings, chombo may be ignored. In serious settings, it may be increased. Often, the chombo penalty is done after the game ends, in order to not waste time during the game.

Hand scoring

Out of all the mahjong variants, riichi has the most complicated scoring system.

  • Hands score han (based on yaku and dora in hand) and fu (based on certain hand composition).
  • A hand scores points based on the han and fu count.
  • Depending on if a hand won on ron or tsumo, other player(s) pay out the hand accordingly.

Naturally, when playing online, the point exchanges are automatically handled. Even some automatic tables are capable of scoring calculations. Otherwise, players go on to memorize the point values, or look at a scoring table.

Dealers receive ~50% more points than non-dealers for all wins. However, if a non-dealer wins by self-draw, then the dealer must pay roughly 50% while non-dealers pay roughly 25% each. The winner of a hand collects any riichi bets on the table and additional points allowed by honba.

Game Rounds

A game is organized into rounds, which are named after winds. Each wind round, every player gets a chance to be a dealer. Like player order, the round's wind rotates from East -> South -> West -> North. For example, East 1 means it is the first round and the first player's dealer turn. East 2 means it is the first round, and the second player's dealer turn. This continues until East 4, then the game continues to South 1.

When a dealer wins the round, the game repeats and one honba is added. So a game at East 1, 4 honba means the dealer won four times in a row. In many rulesets, the dealer also gets to keep the seat if in tenpai (and no one won the round).


Traditionally, games are the length of one hanchan - an East and a South round. Therefore, each player gets two turns to hold the dealer seat.

For shorter games, players may play a single East round. Here players only have the opportunity to hold the dealer seat once. After the conclusion of four wind rotations, then the game is brought to the end. Yet, the points may invoke the extra round and bring the game into the South Round.

End of game

End game results with raw scores and uma scores

Typically, the game ends after the final hand of the last round, when at least one player has at least 30,000 points. This figure may differ (it can vary from ruleset to ruleset). However, the entire game may end prematurely.

A game end may occur under the following conditions:

  • Negative points. When any player's points falls below 0, then the game ends immediately. At that point, the player has run out of point sticks. The game can continue when a player has exactly 0 points. (Some rules allow the game to continue even when a player has negative points)
  • Win and finish. On the final hand of the last round, if the dealer wins the hand, the dealer may choose to continue the game or end the game.
  • Extra rounds. When no player has scored 30,000 points or more, players may opt to continue playing rounds until a player does reach that goal, after which the game ends. (Whether this happens or not will depend on the rules.)

End game score

Once the game ends, points are tallied, and players get a rank from 1st to 4th.

When using the oka and uma systems, players will get a bonus or penalty based on rank. 4th place pays 1st place some amount of points, and 3rd place pays second place some amount of points. These systems were originally designed for gambling, but it can also be used for tournament or competitive play.


Many rules of the game may be subject to various customization and house rules. Many simply resort towards allowing or disallowing certain rules and even hand patterns. Others involve different methods of enforcement and point values.

Three player

Sometimes, games can be played with three players, simply because four players are not available. A modified version to the rules are created to accommodate this scenario.

Two player

For any 1-on-1 situation, even a two-player variation is possible. Though gameplay becomes even more limited than that of the three-player variation. The tile count is even less; and often, it is down to a single suit.

Space Mahjong

A variant that removes limitations regarding terminal tiles by wrapping around, causing them to act like any other numbered tile, while honor tiles also act more like number tiles as well. In addition, you may call chii on any player, as you would with pon.


Washizu mahjong is a variant where three out of four tiles are transparent - other players can see them. This reveals most (but not all) of players' hands.

Buu Mahjong

A variant that is much more fast-paced, and considered more suited towards gambling, with the goal of 'sinking' the other players.

Things to Know

Compared to other "general" variants of mahjong, such as Hong Kong or Singaporean:

  • Yaku are less important for the value of the hand. You need at least one yaku to win, but in general, yaku are less important to focus on. This is because of riichi and dora. By using riichi and/or dora, hands can be valuable without sacrificing much speed. Therefore, slower/more difficult yaku have a harder time competing.
    • The "mangan limit" is another contributing factor. Each han roughly doubles the score until ~4 han (specifically, at 8000 points), where you reach mangan. Past this point, each han become less effective at increasing your score. Therefore, 4 han hands are great for efficiency.
  • Defense is a major part of gameplay, due to riichi and furiten. Furiten allows players to defend reliably. Riichi gives players a reason to defend - they do not want to deal in to a potentially large hand. Also, the gain from tsumo is not that much more than ron.
  • Placement is important in most places where riichi mahjong is played. The oka and/or uma encourage players to rise in place rather than rise in points. Going from 2nd to 1st in the last round might be worth the equivalent of a yakuman, depending on the settings. In online clients, placement is often the main factor for determining rating.

A player new to mahjong should focus on the following:

  • How to make a winning hand.
  • Basic game flow - getting used to gameplay in general.
  • Basic yaku, such as riichi, tanyao, and yakuhai.

Once you learn these, you should learn:

  • Tile efficiency - how to build your hand faster (and when to go for speed over value, and vice versa).
  • Defense - which tiles are safer than others. Also, learn to defend and not just push every hand you get.
  • Common values for scoring and the other yaku. Note that some yaku, like honroutou and sankantsu, are slow, rare, difficult, and not worth very much. Others are more useful.

Player environments

The game may be played under a number of different environments. New players may engage under casual settings where rule enforcement is not so strict, and play speed might not be so rigorous. In addition, the pressure of winning is smaller. The formality is increased under tournament settings. In Japan, commercial play is hosted in mahjong parlors, where players come to pay-to-play. Either at the parlors, casinos, or residences, gambling may be involved, whether it be legal or not legal. Finally, professional play involves televised games; and a staff may take detailed record of games and their results. Naturally, participants are expected to be knowledgeable of the rules and strategies.

Club play



Jansou are known as mahjong parlors. They're generally commercial establishments catered for mahjong play. Most jansou are located in Japan, but a small number are located in the United States. Typically, players enter these establishments to play with a fee. They typically apply their own game rules.

Etiquette practices

A number of etiquette guidelines are in place, both written and unwritten depending on the playing environment. Players are recommended to learn and take heed of these guidelines in order to maintain a positive game atmosphere.


An old hand held Nintendo mahjong game.


Players have been writing about the game as they play it. Topics cover game activity, strategy, and overall experience.


Books on various game subjects have been written. Many focus on player development regarding game strategy and tactics.


The game has been featured in a number of television series and movies.

Video games

A number of video games featuring mahjong have been developed. The history of mahjong video games stretches as far back as the history of video gaming itself. By the 1980's, mahjong has been big enough in Japan, such that it was natural for the game to progress within the then fledgling video game industry.

External links

Japanese mahjong in Japanese Wikipedia
Their Riichi Rules for Japanese Mahjong contains detailed rules and terminology. A previous version was used by Crunchyroll's Saki anime translator.
Barticle's Japanese Mahjong Guide can be downloaded from the downloads section. It contains even more detailed rules and terminology.
JPML ruleset
A Japanese Mahjong blog for English speakers
Rules from the annual Saikyousen tournament
Another blog regarding various aspects of the game.