How to Use Jokers in American Mahjong

Jokers are what make American mahjong feel different from every other style. There are eight of them in a 152-tile set, and a single joker can turn a hopeless hand into a winner. Knowing exactly where jokers can go, when to swap for them and when to hold on to them is one of the quickest ways to improve. This guide covers the rules first, then the strategy.

The one rule to remember

A joker can stand in for any tile in a group of three or more identical tiles:

• a pung (three identical tiles),
• a kong (four identical tiles),
• a quint (five identical tiles), and larger groups such as a sextet on cards that use them.

A joker can never be used:

• in a pair, or
• as a single tile, such as a lone flower, a single number in a "year" hand, or the singles in a singles-and-pairs hand.

That is the whole rule. It applies to flowers, winds and dragons too: a pung of flowers can include jokers, but a pair of flowers cannot.

Why quints need jokers

There are only four copies of each suit, wind and dragon tile. A quint of five identical tiles is therefore impossible without at least one joker. Quint hands are exciting because every joker you hold brings you closer, but they also depend on luck. Flowers are the exception: there are eight, so a quint of flowers can be built from real tiles.

Jokers at the table

In the Charleston

You may never pass a joker, in either Charleston or the courtesy pass. If you are dealt one, it stays with you for the whole hand unless you choose to discard it later.

Calling discards

When you call a discard to complete an exposed group, you may fill the rest of the group with jokers. For example, if someone discards a 5 dot and you hold one 5 dot and one joker, you can call it and expose a pung of 5 dots made of two real tiles and one joker.

A discarded joker, on the other hand, can't be called by anyone, not even to win.

Declaring mahjong

When you declare mahjong, your whole hand, exposed and concealed, must match one pattern on the card exactly, and every joker must sit in a group of three or more. If a joker would have to complete a pair or stand in for a single, the hand is not a win. Our Mahjong Coach's rule check catches this and explains why before you make the mistake at a real table.

Joker swaps

Jokers in exposures don't have to stay there. On your turn, after you draw, you may swap: give the owner of an exposure the real tile that one of their jokers represents and take the joker into your hand. You can swap from anyone's exposure, including your own, and some tables allow several swaps in one turn.

Swapping is powerful because it turns a tile you probably couldn't use into the most flexible tile in the game. Watch for:

• Exposed pungs and kongs of tiles you hold. If someone has exposed three 7 bams with a joker and you draw a 7 bam, that 7 bam is really a joker for you.
• Tiles that are otherwise dead. A tile that fits none of your patterns is a perfect swap tile.

Because of swaps, experienced players think carefully before exposing jokers early. An exposure with jokers is an invitation.

Strategy: keep, use or discard?

Keep them almost always

A joker fits almost every pattern on the card, so it is rarely the right discard. As a rule of thumb, discard a joker only when:

• your hand is dead (it can no longer match any pattern) and you want a safe discard, or
• you are playing a singles-and-pairs hand, where jokers can't be used at all.

Even then, remember that any player can use a joker you discard only as a safe tile: it can't be called, which is exactly why it is safe.

Count your jokers when choosing a pattern

When you pick a target pattern, count how many jokers it could use. A pattern built from pungs and kongs can absorb every joker you hold. A pattern with several pairs and singles can use very few. If you hold three jokers, lean toward pung-heavy hands and quints.

Watch for dead pairs

Because jokers can't help with pairs and singles, those tiles are the hardest part of many hands. If the pattern you want needs a pair of North winds and three North winds are already visible in discards and exposures, that pattern can't be completed. Switch before you waste turns. The Mahjong Coach warns you when your closest pattern needs a pair or single that is no longer available.

The jokerless bonus

Many cards pay extra for a hand completed without any jokers. When you are one or two tiles from mahjong and you still hold a joker you don't need, weigh the bonus against speed. Usually speed wins, but late in a hand with plenty of wall left, waiting for the real tile can pay off.

Reading other players' jokers

Jokers also tell you about your opponents. When a player exposes a group with jokers in it, they are showing you both what they are building and how much help they needed to build it:

• Several jokers in one exposure usually means that player is committed to a pung-heavy or quint hand and is short of real tiles. Their remaining groups are likely to need jokers too, so they will be slow unless they draw well.
• A player who never swaps when they could is often protecting a concealed hand, or holding a pattern that can't use the joker.
• A player who discards the real tile that would free a joker from someone's exposure is either careless or no longer interested in that suit and number. Either way it is a clue.

Use this when choosing discards late in the hand. A tile that would complete a joker-filled exposure's family is more dangerous than one that doesn't fit anything on the table.

Common joker mistakes

1. Planning a pair around a joker. It feels natural to count a joker as "any tile", but a pair or single must be two real tiles or one real tile. Check the pairs in your target pattern first.
2. Exposing jokers too early. An early exposure full of jokers invites every other player to swap them away. If you can wait a turn or two for a real tile, it often pays.
3. Forgetting to swap. Beginners often discard a tile that could have been exchanged for a joker. Before each discard, scan every exposure on the table.
4. Discarding a joker "to be safe". A joker is safe only because nobody can call it, but it is also the most useful tile you will ever hold. Save that move for a dead hand.
5. Chasing jokerless at the wrong time. The bonus is nice, but a quick win with a joker usually beats a slow one without.

Quick reference

Practise with jokers

The Mahjong Coach's American table follows every one of these rules. The coach panel shows how many jokers you hold and how many your closest pattern can use, the rule check stops a mahjong that puts a joker in a pair or a single, computer opponents swap jokers out of your exposures when they can, and the review explains discards on the "tiles away from your nearest pattern" scale. The practice patterns are written by Mahjong Station. To practise your own card's hands, enter them privately in My card.