Mahjong Calculator
Tap tiles, watch your shanten and waits update live, and get a clean yaku breakdown the moment you win. Pick your rule set — Riichi, Hong Kong, Taiwanese, or Chinese Official (MCR) — and play the way you actually play.
8 tiles away from tenpai.
The final tile you add becomes the winning tile.
Four mahjong variants, one calculator
Each variant has its own dedicated landing page with the calculator, full scoring rules, a worked example, and a reference list of every pattern. Pick the one you actually play:
Han + fu scoring with riichi declarations, dora, and yakuman caps. The dominant competitive variant in Japan and across EMA.
81 fan patterns with strict exclusion rules and an 8-fan minimum. The variant used at world championships since 2002.
Casual Cantonese rules with exponential 2^faan payouts. The variant most families actually play.
Five melds plus a pair instead of four — bigger hand, faster draws. The variant played throughout Taiwan.
No honor tiles, no chi calls, mandatory missing-suit rule. The fastest variant in widespread play — popular across mainland China via mobile apps.
How the four variants score
| Variant | Hand | Unit | Patterns | Min to win | Played in |
|---|---|---|---|---|---|
| Riichi | 14 tiles | Han + fu | ~33 yaku | 1 yaku | Japan, online apps |
| MCR | 14 tiles | Fan | 81 fan | 8 fan | World tournaments |
| Hong Kong | 14 tiles | Faan (2^faan) | ~27 faan | 3 faan | HK, Guangdong, diaspora |
| Taiwanese | 17 tiles | Tai | ~13 tai | none / 1 tai | Taiwan, Fujian, diaspora |
| Sichuan | 14 tiles | Fan (2^fan) | ~20 patterns | 1 fan | Sichuan, mainland CN mobile |
Want the deep dive? See all variant comparisons →
Common questions
How do I use the calculator?+
Pick your rule set (Riichi, MCR, Hong Kong, or Taiwanese), then tap tiles from the tile picker to build your hand. The calculator shows your shanten count and which tiles you're waiting on in real time. When the hand reaches a winning structure, mark the winning tile and choose ron or tsumo — you'll get a full breakdown of every scoring pattern that applies.
Which mahjong variant should I use?+
If you're learning Japanese mahjong, anime style, or playing online via apps like Tenhou or Mahjong Soul → Riichi. If you're at a Hong Kong / Cantonese home table → Hong Kong. If you're playing in Taiwan or at a Taiwanese family table → Taiwanese 16-tile. If you're playing in international or Chinese tournaments → MCR (Chinese Official).
Is the calculator free? Do I need to sign up?+
Yes free, no signup. The calculator runs entirely in your browser — no account, no app to install, no tile data leaves your device. Ads on the page keep it running.
Does it work on mobile?+
Yes — the tile picker and hand display are designed to work on a phone, including the small details like passing the phone around the table. Bookmark it to your home screen for one-tap access.
Can I share a hand with someone?+
Yes. Every hand state is encoded in the URL hash, so you can copy the current page URL after building a hand and share it. The recipient opens the link and sees the exact same hand.
Why are there so many mahjong scoring systems?+
Mahjong started in mid-1800s China and spread regionally, picking up local conventions along the way. Riichi evolved separately in post-war Japan with its unique riichi/fu mechanics. Hong Kong kept the older, simpler faan structure. Taiwan added an extra meld to make the 16-tile variant. MCR was created in 2002 by the World Mahjong Sports Games to standardize for international play. None is more correct than the others — they're separate games.
Full pattern references
Every yaku, fan, faan, and tai pattern across the four variants — with worked example hands you can open directly in the calculator.