Mahjong
Full 4-player riichi vs 3 CPUs (East round)
Mahjong
Full 4-player Japanese riichi mahjong vs 3 CPUs (East round). Riichi, calls, dora, full yaku & yakuman scoring — play instantly in the browser.
📖 How to Play
- From 13 tiles, draw and discard one toward 4 sets + 1 pair
- Call Pon/Chi/Kan on discards; declare Ron on a winning discard
- A closed tenpai hand can declare Riichi (1000-pt bet, ura-dora chance)
- Self-draw your winning tile to Tsumo — you always need at least one yaku
- Tap a tile then tap again to discard; Tsumo/Ron/calls are buttons
- East round (E1–E4); final scores set your placement and feed the leaderboard
About this game
This is Japanese riichi mahjong played against three CPU opponents with the full 136-tile set. From a 13-tile hand you draw and discard toward the standard shape of four sets plus a pair. It's an East round (hands E1–E4), so a game finishes faster than a full hanchan.
Japanese rules and scoring are implemented in full: winning by tsumo or ron, calling pon/chi/kan, declaring riichi on a closed tenpai hand, dora and ura-dora, and yaku detection with fu calculation all the way from pinfu and chiitoitsu up to yakuman.
The CPU comes in three strengths. It calculates tile efficiency (which discard moves it closest to tenpai) and reads danger tiles to decide whether to push or fold — including folding outright when someone declares riichi, which makes matches feel like real games rather than scripted ones.
Tips & strategy
- You cannot win without at least one yaku — always check that your completed shape actually scores
- Riichi on a closed tenpai hand is powerful: it adds value and opens the ura-dora draw, which can multiply your score
- Calling tiles lowers both your value and your defence, so growing a closed hand is often worth more than a fast cheap one
- When an opponent declares riichi and your hand is cheap or far from ready, fold with known-safe tiles instead of pushing
- An East round is only four hands, so a single big win can decide your placement
- Discards stay visible on the table — just reading what opponents have thrown improves your danger reads
FAQ
Q. How long is a game?
A. It's an East round (hands E1–E4), shorter than a full hanchan — roughly 10–20 minutes.
Q. Are yaku and scoring implemented?
A. Yes — tsumo/ron, pon/chi/kan, riichi, dora and ura-dora, and the full yaku set with fu calculation up to yakuman.
Q. Can I choose the CPU strength?
A. Yes, three levels. The AI computes tile efficiency and reads danger tiles to decide whether to push or fold.
Q. What are the controls?
A. Tap a tile to select it, then tap again to confirm the discard. Tsumo, ron and calls are on-screen buttons.
Q. Can beginners play?
A. Yes. When your hand is complete the Tsumo/Ron buttons appear automatically, so you can play without memorising yaku or scoring — all point calculation is handled for you.