Mahjong School American · NMJL Standard
Training & Practice

Opening Discard Trainer

Read a 13-tile opening hand and pick the tile you would discard first, then see why. The drills use only general, public-domain principles: keep what connects, shed what is isolated. Bring your own card for exact lines. Your best score is saved on this device.

Trainers · Opening Discard Trainer
Member · all 8 drills + endless rack generator Free: four drills. A membership unlocks all eight plus an endless rack generator.
Drills
Read the hand below and choose your first discard.

Members-only drills & generator

Scenarios 5–8 and the endless rack generator are part of the member plan. Upgrade to open the full set and keep practicing.

See membership →
How the trainer works & what it does not do

The eight drills are opening racks with one well-supported first discard and the reasoning behind it. The endless generator builds fresh racks from generic tile shapes and points to the lowest-support tile (the one with the fewest connections to the rest of the hand).

Nothing here reads the official NMJL card. The trainer teaches the habit of finding your weakest tile — not the exact score of any year's hands. Your purchased card stays the authority on what a hand is worth. No card data is stored or sent.

About the Opening Discard Trainer

The Opening Discard Trainer gives you eight opening-rack scenarios and asks you to pick the right first discard, with the reasoning.

Four are free; the full set and an endless rack generator come with membership. It turns the most important early decision into something you can practice on repeat.