Riichi Mahjong · Yakuman（closed only）

Tenhou (Blessing of Heaven) in Riichi Mahjong: Rules and Odds

In riichi mahjong, Tenhou (blessing of heaven) is a yakuman: when the dealer picks up their 14 starting tiles, they already form a complete hand, so the dealer wins by tsumo without discarding a single tile. It's pure luck, and one of the rarest yakuman of all.

The rules for Tenhou

• Dealer only; a non-dealer winning on their first draw gets chiihou
• The 14 starting tiles must be complete: four sets and a pair, seven pairs or thirteen orphans all count
• No calls or kans before it (a dealer who makes a closed kan and wins on the replacement tile doesn't get tenhou)
• No other yaku needed — tenhou is a yakuman by itself

How Tenhou is scored

The yaku and points below are computed live by the same scoring code the game uses.

Because it's a yakuman, ordinary yaku (pinfu, tanyao, dora…) don't add anything; if a hand-shape yakuman (suuankou, kokushi musou…) is also there, the multiples add up.

Tenhou odds

We shuffled the 136 tiles and drew 14 at random (a dealer's starting hand) 50,000,000 times and counted how often they were already complete:

Source: 50,000,000 random 14-tile hands.

• 152 of 50,000,000 hands were complete: 0.0003%, about once in 329,000.
• The dealer seat comes round about eight times in a hanchan, so even a heavy player may never see one.
• The chance of being tenpai with 14 tiles (discard one and riichi) is 0.070% — that's the chance for double riichi.

Heavenly hand in other mahjong styles

• Sichuan mahjong: heavenly hand, straight to the cap (Sichuan mahjong Heavenly Hand)
• Taiwanese mahjong: heavenly hand, 24 tai (Taiwanese mahjong scoring)
• Hong Kong mahjong: heavenly hand, straight to the limit (Hong Kong mahjong fan table)

To try your luck, open a table of free online riichi mahjong — the computers play with you and count the points for you.

FAQ

Is tenhou a single or double yakuman?

Single on this site. If a hand-shape yakuman such as suuankou or kokushi musou comes with it, the multiples add up.

What are the odds of tenhou?

A random 14-tile hand is complete about 0.0003% of the time, roughly once in 329,000 (from 50,000,000 random deals on this site).

Is it tenhou if a non-dealer's starting hand is complete?

A non-dealer only has 14 tiles after their first draw. Winning on that first draw is chiihou, also a yakuman.

Related yaku

Chiihou Yakuman（closed only） A non-dealer wins on their first draw: the rules, what stops it, chiihou vs tenhou and renhou, and the odds. Double Riichi 2 han（closed only） Riichi on your first discard for 2 han instead of 1: the rules, what stops it, examples and the odds of a tenpai start.