How to Read Discards in Riichi Mahjong (Beginner's Guide)
Reading the river separates intermediate players from beginners. Every discard leaks information about the hand's shape — here is how to extract it.
What does "reading discards" mean?
Reading discards (yomi, 読み) is using the tiles an opponent has thrown out to infer what they are holding and waiting on. Each discard rules out certain hand shapes — the longer the river, the more constrained their hand. The goal is not to guess the exact wait; it is to narrow the danger zone enough to pick safe discards.
What does the order of discards tell you?
Early discards (turns 1-6) are usually tiles a player has no use for at all — honors of the wrong seat, isolated terminals. Mid-river discards (turns 6-12) shed tiles after the shape is partly formed, so they are the most informative. Discards immediately around a riichi or call usually mean the player just tightened their wait. Mid-river is where most reads live.
How do you read a riichi declaration's wait?
The sideways tile pins the moment of declaration — everything before it is open hand-building, everything after is forced discards from a locked shape. Walk the pre-riichi river and ask: what shapes are consistent with all of those discards? Apply suji (if 5 is discarded, 2 and 8 are safer against a ryanmen on that suit) and kabe (if all four 5s are visible, no 4-7 ryanmen relies on 5). What is left is the danger zone.
What is the difference between picking safe tiles and reading waits?
Safe-tile selection is reactive: which of the tiles in my hand are least likely to deal in right now? Reading waits is constructive: based on the river, what shape is the opponent most likely holding? You often do not need a full read — genbutsu plus suji is enough. Reading waits matters when no fully-safe tile exists and you need a probabilistic best guess.
When should I start reading discards seriously?
Start the moment any opponent declares riichi or pons a yakuhai — both are commitment signals. Also when your own hand falls behind (2-shanten or worse) and you have already given up on winning the round. Reading is mental effort; spending it on rounds where you might deal in pays off, spending it on hands where you will win first does not.