Some hands are easy: two tiles in a row, wait on either end, done. Others hide waits you'd never spot at first glance. This calculator checks all 34 tiles one by one and tells you exactly which ones finish your hand. It's a free tool from Mahjong Academy, and it's handy both at the table and when you're studying.
On this page
How to use it
- Tap tiles in the picker to build your hand, or type it in. Numbers go before the suit:
mfor characters,pfor dots,sfor bamboo andzfor honors (1–7 are East, South, West, North, Red, Green, White). So123m 55zmeans 1-2-3 of characters and a pair of Red dragons. - Enter 13 tiles for most styles, or 16 tiles for Taiwanese mahjong. If you've already called some sets, just enter the tiles still in your hand: 10, 7, 4 or 1.
- Tick seven pairs or thirteen orphans if your rules allow those hands, then press Calculate.
Every result has its own link, so you can send a tricky hand to a friend and argue about it together.
What counts as a wait
A hand is ready (tenpai) when one more tile would make it a winning hand: four sets and a pair, or five sets and a pair with 16 tiles. The tiles that would finish it are your waits. If this idea is new, the ready hand lesson walks through the five basic waits with pictures.
The calculator doesn't care about scoring or whether your rules need a minimum hand value. It only answers one question: does this tile make a complete shape?
Reading the result
You'll see two numbers: how many kinds of tile you wait on, and how many tiles are left. Each kind has four copies, and any you hold yourself can't come to you. So a wait on and with none in your hand is 2 kinds, 8 tiles.
Kinds alone can fool you. A two-kind wait where you hold three of one of them is barely better than a single wait. Always look at the tile count. The calculator only knows your own hand, though: subtract any copies you can see in the discards yourself.
Waits that are easy to miss
These shapes are where the calculator really earns its keep:
Long runs of one suit hide the most waits. Whenever you hold five or more connected tiles in a suit, it's worth checking.
Frequently asked questions
Does it work for Japanese, Taiwanese and Hong Kong mahjong?
Yes. A winning shape is the same everywhere: sets plus a pair. Use 13 tiles for most styles and 16 for Taiwanese, and switch seven pairs and thirteen orphans on or off to match your rules. The only exception is American mahjong, which uses a card of set hands instead.
Why does it say my hand isn't ready?
It needs more than one tile to be complete. The result tells you how many steps away you are; open the shanten calculator to see which discard gets you closer fastest.
Does it count tiles in the discards?
No, only the ones in your hand. Take away what you can see on the table to get the real number.
Ready to practise for real? Pick a style on the Mahjong Academy homepage and play a free game against the computer.