Question 1

How do I use a mahjong calculator?

Accepted Answer

Enter or pick tiles. 13 tiles auto-run wait analysis; 14 tiles auto-run discard analysis—no mode toggle. You get shanten, waits, ukeire, and discard suggestions instantly.

Question 2

How do you calculate shanten?

Accepted Answer

Shanten counts how many effective swaps your hand needs to reach tenpai. 0 shanten means tenpai (ready to win). Mahjong Lab calculates shanten for standard, seven-pairs, and thirteen-orphans forms automatically.

Question 3

How do I find mahjong waiting tiles?

Accepted Answer

Use 13-tile Normal Analysis mode. After you enter 13 tiles, the calculator lists every tile that completes your hand or improves your wait, including multi-sided and complex waits.

Question 4

How do I find the best discard?

Accepted Answer

Use 14-tile Discard Analysis mode. The calculator compares each possible discard and shows shanten and acceptance after every cut, so you can pick the most efficient tile to discard.

Question 5

What's the difference between 13-tile and 14-tile analysis?

Accepted Answer

13 tiles = wait analysis (shanten, waits, ukeire); 14 tiles = discard analysis. Mode follows count—no manual switch.

Question 6

How do I write a hand code?

Accepted Answer

Use m/p/s/z for man, pin, sou, and honors, and write digits 1–9 together. Example: m345678p2346s3456. The hand-code field stays visible, so you can paste anytime.

Question 7

Why is there no tenpai vs discard mode toggle?

Accepted Answer

Mode is inferred from the tile count only: 13 tiles open wait analysis, 14 tiles open discard analysis. There is no separate mode control.

Question 8

How are shanten and tenpai related?

Accepted Answer

Shanten 0 means tenpai. Higher shanten means farther from winning. The analyzer shows both shanten and ukeire so you see how many steps remain and which draws help.

Question 9

What is ukeire (acceptance)?

Accepted Answer

Ukeire is the set of tiles (and remaining copies) that improve the hand—lower shanten or reach tenpai. More tiles usually means better efficiency; discard ranking compares post-discard shanten first, then ukeire.

Question 10

Can I share analysis results?

Accepted Answer

Yes. Copy the hand code to share it, or use “Share as a discard challenge” to make a drill. Opening the link restores the same hand and analysis. To have a friend answer that same hand, send it through Friend Challenge.

Question 11

Are red fives / sanma supported?

Accepted Answer

Neither aka-dora (red fives) nor sanma (three-player mahjong) is supported. Analysis targets standard four-player riichi. If a 0 in a hand code is accepted, it is counted as a normal 5 at most: no aka scoring and no sanma rules. Future support is not promised.

Mahjong Hand Calculator

Results

Hand Analysis FAQ