This (incomprehensive) reference guide is based on Hong Kong gameplay.
There is no such thing as an offical version of mahjong. The game should be played according to player consensus.
Quick links:
The following diagrams show a top-down view of the initial four-wall layout. The numbered markers indicate (for each dice roll total) the initial position for drawing tiles.
The tile icons used in this guide are licensed under CCΒ BY-SAΒ 4.0, being modified (through the use of SVGO for minification) from SVG Oblique illustrations of Mahjong tiles by Cangjie6 and others. See the mahjong-tiles-svg repository for details.
As fallback, characters from the Mahjong Tiles Unicode block (U+1F000 through U+1F02C) are used for the alt text.
, 
, 
, 
, 
, 
, 
, 
= [one through nine]
, 
, 
, 
, 
, 
, 
, 
, 
= [one through nine]
, 
, 
, 
, 
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, 
= [one through nine]
ζ± = East
ε = South
θ₯Ώ = West
ε = North
η΄
δΈ = Red-Centre [red]
η½ζΏ = White-Board [white]
ζ’
= Plum
θ = Orchid
θ = Chrysanthemum
η«Ή = Bamboo
ζ₯ = Spring
ε€ = Summer
η§ = Autumn
ε¬ = Winter
Three consecutive tiles of the same numbered suit.
E.g. , , .
Three of the same tile.
E.g. , , , .
Four of the same tile, called a ζ§ kong.
E.g. , , , .
A concealed kong cannot be robbed for a win, except when the win is a εδΈεΉΊ (Thirteen Littles).
A transparent kong can be robbed for a win.
The conventional threshold for a hand to be winning is a minimum of threeΒ fΓ‘n (ηͺ, or points).
The conventional maximum for scoring is an upper limit of thirteenΒ fΓ‘n, quite often reduced to an upper limit of eightΒ fΓ‘n.
Regular winning hands consist of four melds plus a pair called ηΌ ngΓ‘n (eyes). By itself, such a win is worth zeroΒ fΓ‘n. To raise the number of fΓ‘n, you need to go for one of the patterns below or an irregular hand, and/or rely on bonuses.
The default pattern: four melds plus a pair.
E.g. ,
assuming no bonus for North.
All melds are sequences.
E.g. .
All melds are triplets or quadruplets. Not counted for ζΈ δΈθ²ηͺε (Pure-One-Suit Honours).
E.g. .
All tiles are the same numbered suit, plus honours.
E.g. ,
assuming no bonus for West.
(Triplet or quadruplet) melds in two of the three dragons, plus eyes in the remaining dragon.
E.g.
.
(Triplet or quadruplet) melds in three of the four winds, plus eyes in the remaining wind.
E.g. .
In this example the requirement for ζ··δΈθ² (Mixed-One-Suit) is also met,
so the hand is worth 6 + 3 = 9Β fΓ‘n.
All tiles are the same numbered suit.
E.g. .
(Triplet or quadruplet) melds in all three dragons.
E.g.
.
All tiles are honours.
E.g. .
Bonuses for winds and dragons are counted separately.
(Triplet or quadruplet) melds in all four winds.
E.g. .
All four melds are quadruplets.
E.g. .
Seven distinct pairs.
E.g. .
One & nine of each numbered suit, plus each of the four winds, plus each of the three dragons, plus a duplicate.
E.g. .
A (triplet or quadruplet) meld in a wind tile matching the player's position. Not counted for ε°εεοΌε€§εε (Lesser Three Joys / Greater Three Joys).
E.g. for the player to the right of the dealer.
A (triplet or quadruplet) meld in a wind tile matching prevailing table wind. Not counted for ε°εεοΌε€§εε (Lesser Three Joys / Greater Three Joys).
E.g. when West is the prevailing wind.
A (triplet or quadruplet) meld in a dragon tile. Not counted for ε°δΈε οΌε€§δΈε (Lesser Three Duxes / Greater Three Duxes).
E.g. .
A quadruplet meld. (Omitting this bonus may lead to more strategic play, in the form of refusing a kong to keep an in-hand triple concealed.)
E.g. .
Winning tile is drawn from the wall, not discarded.
No flowers (in games played with flowers).
A flower matching the player's position (in games played with flowers). Not counted for δΈθΊθ± (A Platform of Flowers).
E.g. for the player opposite the dealer.
No revealed melds prior to win.
Winning tile is revealed when completing a transparent kong (or even a concealed kong if the win is εδΈεΉΊ (Thirteen Littles)).
Winning tile is drawn as the compensating tile after a kong (accumulates with consecutive kongs).
Winning tile is drawn as the final tile of the wall.
Either four flora or four seasons (in games played with flowers).
E.g. .
Dealer wins with initial hand.
Non-dealer wins on dealer's first discard.
Scoring is complicated. See Conway's mahjong-scorer readme, in particular the Details section.