向聽 (shanten) is the number of useful tiles a hand still needs before it is ready (聽牌); a ready hand is 0. It decides your discards, because the tile that keeps the count lowest is usually the one to let go. It also tells you when a big hand is too far away to chase and when to play safe instead.
How to do it
1.
Count the finished sets already in the hand: runs (順子) and triplets (刻子).
2.
Count the partial sets, two tiles one draw from a set (6-7, 6-8, or two of a kind), and decide whether one pair is your pair. Sets and partials together stop at five.
3.
Work out (5 − sets) × 2 − partials − pair, where pair is 1 if you have one and 0 if not. The result is the distance; 0 means the hand is ready.
4.
Try other ways of grouping the tiles and keep the lowest number, then check it by finding a real path: name the tiles you would draw, one per step, until the hand is ready.
Four sets: 1-2-3 and 4-5-6 of characters, 7-8-9 of dots and 2-3-4 of bamboo. 6-7索 is a partial and the two 中 are the pair. (5 − 4) × 2 − 1 − 1 = 0, so the hand is already ready, waiting on 5索 or 8索.
1 away: one draw from ready
1 away
wait
Let go
Three sets (1-2-3 and 4-5-6 of characters, 7-8-9 of dots), two partials (2-3索 and 6-8索), the 中 pair, and a lone East wind that helps nothing. (5 − 3) × 2 − 2 − 1 = 1. The path: draw 7索 into the gap to make 6-7-8索, let the East wind go, and the hand is ready on 1索 or 4索.
3 away: a hand still taking shape
3 away
wait
Let go
Only two sets, 1-2-3萬 and 7-8-9筒. Two partials: 1-3筒, which wants 2筒 in the middle, and 4-5索. The pair is East, and 6萬, 9索, West and 發 are loose. (5 − 2) × 2 − 2 − 1 = 3. One path: 2筒 fills 1-3筒, then 7萬 and 8萬 grow the 6萬 into 6-7-8萬; let 9索, West and 發 go, and the hand is ready on 3索 or 6索. Three draws, as the count said.
Common mistakes
• Counting more than five groups. Sets and partials stop at five, so a sixth partial does not lower the distance.
• Forgetting the pair. Four sets and two partials with no pair is not ready; it is still 1 away.
• Stopping at the first grouping. The same tiles can often be grouped several ways, and the distance is the lowest any grouping gives.
• Mixing up distance and waits. 向聽 counts the draws you still need, not how many different tiles could help.
Practice now
Below is the app's distance drill at Novice (入門), the free tier: ten sorted hands, each at most two tiles from ready. The real game engine works out every answer and, after each hand, draws one path to ready.
聽牌 is the state of being one tile from a win. 向聽 is the distance to that state: how many more useful tiles you need before you are 聽牌. A 聽牌 hand is at 向聽 0, and players call a hand one step away 一向聽.
How do you count shanten for a 16-tile Taiwanese hand?
Use (5 − sets) × 2 − partials − pair, with sets plus partials capped at five and pair counted as 1 if you have one. Try each way of grouping the tiles and keep the lowest result.
Is shanten counted the same way in 13-tile mahjong?
The method is the same, but a 13-tile hand needs only four sets, so its formula is (4 − sets) × 2 − partials − pair, with sets and partials capped at four. With one more set to build, a freshly dealt 16-tile hand usually starts further from ready.
Does 向聽 count the tiles I discard?
No. Each turn is one draw and one discard, and 向聽 counts only the draws that move the hand forward. A hand 3 away needs at least three useful draws, and more if the wall gives you the wrong tiles.