How does a joker exchange work in mahjong?

Last updated November 12, 2026

On your turn, after you draw or call and before you discard, you may give the real tile a joker stands for and take that joker from any exposure on the table, including your own. You can swap more than once in a turn, but never with a discard and never after you have thrown.

Step by step

1. Draw from the wall, or call a discard.
2. Look at every exposure on the table for a joker whose tile you hold.
3. Put your real tile into that exposure and take the joker onto your rack.
4. Repeat if you can make another swap.
5. Discard, or declare mah jongg if the joker finished your hand.

Whose exposures can you swap from?

Anyone's. An opponent's exposures, your own, and the legal exposures of a player whose hand is dead all count. The tile must be exactly the one the joker stands for: a joker in a kong of 5 Bams only comes out for a 5 Bam.

What you cannot do

• Use a discard. You cannot call a thrown tile to swap it for a joker.
• Swap out of turn, or after you discard.
• Take a joker from tiles still hidden on someone's rack. Only exposed jokers can be swapped.
• Take the joker from the exposure that made a hand dead. That group goes back to its owner's rack.

Where tables play it differently

• After a call. League rules let you swap after you call a discard as well as after you draw. Some home tables allow it only after a draw.
• Your own exposures. League rules allow it. A few casual tables do not, so ask.
• Dead hands. League rules keep the jokers in a dead hand's legal exposures available. Some tables freeze every tile on a dead rack.

A worked example

South has this pung exposed:

On your turn you draw a 7 Crak. You hand it to South's pung and take the joker. Your own rack shows a kong with a joker in it, and you also hold a 2 Dot:

You swap that one too. Now you hold two free jokers, and only then do you discard. If you had thrown first, both swaps would have had to wait until your next turn.