You guys have had a lot of questions about how to do a Joker exchange, who can do a Joker exchange, when to do a Joker swap, and what happens if you miss one…so let’s dig into it!!
During the mahjong game, when a tile is called, a Joker or Jokers may be used as part of the exposure of tiles to make up the grouping, as long as it is three or more like tiles in the grouping.
When a Joker is exposed on top of a player’s rack, that Joker is available for Joker swap or Joker exchange. Any player at the table, including the player who exposed the Joker, can swap the represented tile for the exposed joker, and then take that Joker back into the sloped part of their rack. Joker swaps must be done on the players turn. If a possible Joker exchange is missed, unfortunately that discarded Tile cannot be called to make the Joker swap. 
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