Mahjong Defense: Reading Danger and Avoiding Deal-Ins

Practical defense for riichi mahjong β€” dangerous discards, the furiten rule, genbutsu tiles, and when to fold.

Why defense matters

In riichi mahjong, paying a ron can cost 3,000 to 18,000+ points. Knowing when to stop attacking and switch to defense is the single biggest skill difference between beginners and strong players.

The furiten safety net

A player who has discarded any of their winning tiles is in furiten and cannot win on a discard. Once you spot furiten, every tile in their discard pile becomes 100% safe against their ron.

Genbutsu and the easiest fold

Genbutsu β€” tiles that player has already discarded β€” are completely safe. The next-safest are tiles one rank away from their discards (suuji), and honors they have passed. This site highlights your furiten status so you can fold with confidence.