Taiwanese Mahjong · 1 tai

Concealed Hand (Men Qing) in Taiwanese Mahjong: Tai, Examples and Odds

In Taiwanese mahjong, a concealed hand (門清, men qing) is worth 1 tai: from the deal to the win you never chow, pung or make an exposed kong — every tile in your hand is one you drew — and you win on someone else's discard. A concealed hand that is self-drawn is not concealed plus self-draw; it becomes a concealed self-draw (不求人), 3 tai.

The rules for Concealed Hand

• No chows, no pungs, no exposed kongs anywhere in the hand (an added kong counts as exposed)
• A concealed kong keeps the hand concealed: you drew all four tiles; you only lay them down to draw a replacement
• The winning tile comes from someone else's discard; a self-draw scores as Concealed Self-Draw
• Flowers don't matter; replace them as usual

How Concealed Hand is scored

The tai below are computed live by the same scoring code the game uses (dealer and dealer-streak tai are added on top).

Common combinations:

How it relates to other hands

• Concealed Self-Draw: concealed and self-drawn scores 3 tai, replacing the concealed hand and the self-draw; the three are never added together.
• Ping Hu: a concealed ping hu is common, 3 tai together. Ping hu itself doesn't require a concealed hand — chows are allowed.
• Single wait: a concealed single, edge or closed wait adds single wait, 1 tai.
• Concealed pungs: every pung in a concealed hand was drawn yourself; unless it was completed by the winning discard, it counts as a concealed pung.
• Heavenly, Earthly and Human hands: these are concealed by nature but score as Heavenly / Earthly / Human hand instead; the concealed hand is not added.

Concealed Hand odds

We let four computers play 12,000 hands on this site's table (normal level); 11,677 of them ended with a win:

• Only about one win in ten is concealed: the computers chow and pung whenever they can, so most wins already have claimed sets.
• Wins with a concealed hand averaged 1.9 tai for the whole hand; all wins averaged 1.6 tai.
• These numbers reflect a fast table. Human players keep their hands concealed more often, so the share is usually higher.

When it pays to stay concealed

Claiming can save a turn or two, but staying concealed is worth tai on its own:

• Winning on a discard: the concealed hand adds 1 tai.
• Self-drawing: concealed it's a concealed self-draw for 3 tai; after claiming, a self-draw is only 1 tai — the biggest difference.
• A strong start: if you're one or two tiles from ready, there's no need to give up the concealed hand for one chow.
• Still far away after claiming: a chow saves just one tile; with a scattered start, claiming won't speed you up much, so you may as well stay concealed and draw.
• When to claim: someone else is already ready, the wall is running out, or the claim makes you ready on a good wait — then speed matters more.

To practise the trade-off, open a table of online Taiwanese mahjong — the computers play with you and count the tai for you.

Concealed Hand in other mahjong styles

• Japanese mahjong: a concealed hand is not a yaku by itself — you need riichi or another yaku to win; a concealed self-draw is "Menzen Tsumo", 1 han (Japanese mahjong yaku list)
• Hong Kong mahjong: concealed hand is 1 fan, plus 1 fan for a self-draw (Hong Kong mahjong fan list)
• Chinese Official (Guobiao): Concealed Hand is 2 fan; a concealed self-draw is "Fully Concealed Hand", 4 fan (Guobiao fan list)

FAQ

How many tai is a concealed hand?

In Taiwanese mahjong a concealed hand is worth 1 tai: no chows, pungs or exposed kongs, won on a discard.

Does a concealed kong break a concealed hand?

No. You drew all four tiles of a concealed kong yourself and only lay them down to draw a replacement. Exposed and added kongs do break it.

How many tai is a concealed self-draw?

A concealed self-draw (不求人) is 3 tai, which already includes the concealed hand and the self-draw.

Is a hand with flowers still concealed?

Yes. Flowers are just replaced and have nothing to do with being concealed; your own seat flower scores 1 tai separately. But any flower rules out ping hu.

Related hands

Concealed Self-Draw 3 tai Never claim a tile and self-draw the win — 3 tai. Concealed hand vs self-draw, concealed kongs and replacement wins, and how often it happens. Self-Drawn 1 tai Drawing your own winning tile — 1 tai, paid by all three opponents. Self-draw vs concealed self-draw, scoring combos and how often it happens. Ping Hu 2 tai Five chows, no honors, no flowers, two-sided wait, no self-draw — a 2-tai hand. Checklist, common mistakes and odds.