House rules

No two mahjong tables score quite alike. These are the differences that come up most, roughly in order of how often they cause an argument. Where the calculator has a setting for it, it says so.

The minimum

Most Hong Kong games are played 三番起糊: a hand needs three faan to be declared. Some casual tables play to one faan, or with no minimum at all, which allows the chicken hand (雞糊). A higher minimum makes for slower, bigger hands.

Calculator: House rules → Minimum to win.

The limit

Scores are capped, most often at 8, 10 or 13 faan. The limit hands (thirteen orphans, nine gates and the rest) score whatever the cap is. With a 13-faan cap, some of them are worth less than 13; the faan table shows each one's value.

Calculator: House rules → Limit.

Half-spicy or full-spicy

This decides how fast points grow with faan. Half-spicy is the usual Hong Kong choice. Full-spicy makes big hands score enormously. The points tables show both.

Who gives the points on a discard

Under 全銃 the discarder gives all the points; under 半銃 they give half and the other two share the rest. Discarder-gives-all is tougher on careless discards and is common in Hong Kong games.

What counts as a common hand

All tables agree that a common hand is four chows and a pair. Some also insist that the pair isn't a scoring honour, or that the hand holds no flowers. A few value it at 3 instead of 1. The calculator uses the plain rule: four chows, 1 faan.

Seven pairs

Seven pairs (七對子) isn't part of traditional Hong Kong scoring, but many tables allow it, usually for 4 faan. It's off by default; turn it on under House rules → Extra patterns.

Flower wins

Some tables let a player who collects seven of the eight bonus tiles take the last one from whoever holds it and win (七搶一), and treat all eight (八仙過海) as an instant win. What they score varies from a few faan to the limit, so the calculator doesn't count them. Agree a value first.

Liability

Under 包 (baau1), a player who feeds someone the discard that completes a dangerous hand takes the whole loss for the table. Typical cases are giving a third dragon pung, or the last exposed set of a pure suit. The details differ a lot between groups and the calculator doesn't model them.

Two winners on one discard

Some tables let only the player next in turn win (截糊); others let everyone who can win take it, and the discarder gives points to each of them.

False wins

Declaring a hand that isn't complete (詐糊) usually costs points. A common rule is that the player gives every other player the points for a limit hand, but tables vary.