What is Yaku? Hand Patterns Required to Win in Mahjong Explained for Beginners

What is Yaku (Hand Pattern)?

Yaku (役) refers to specific tile combination patterns required to win (agari) in mahjong. Even if you complete a 4 sets + 1 pair formation, you cannot win without at least one yaku. This is a fundamental rule of mahjong.

Yaku ranges from 1 han patterns to yakuman, with points (han) assigned according to difficulty. You can aim for higher scores by combining multiple yaku.

Detailed Explanation of Yaku

Basic Concept of Yaku

Classification of Yaku

By han count:
- 1 han yaku: Most basic patterns
- 2 han yaku: Somewhat stricter conditions
- 3 han yaku: Relatively difficult patterns
- 6 han yaku: Guaranteed haneman
- Yakuman: Highest scoring (equivalent to 13 han)

By establishment conditions:
- Closed yaku: Only when not called
- OK when called: Open hand possible
- Lucky yaku: Depend on draw/tiles
- Building yaku: Aim to construct

Basic Yaku Beginners Should Learn

Usage Examples

Real Game Situations

Example 1: Checking Yaku

"Do you have yaku?"
"Riichi, tsumo, dora 1 for 3 han"
"Just yakuhai white"

Example 2: No Yaku Situation

"Ah, no yaku!"
"Shape is complete but no yaku"
"Watch out for yakunashi chombo"

Example 3: Compound Yaku

"Riichi, ippatsu, tsumo, pinfu, dora 2"
"Tanyao, sanshoku, dora 3 for mangan"
"2 yakuhai for double east, double south"

Related Terms

• Han: Point unit for yaku
• Menzen: Closed hand state
• Kuisagari: Han decrease when calling
• Yakuman: Highest scoring yaku
• Dora: Not yaku but increases han

Common Mistakes and Points to Note

Points Beginners Often Mistake

1. Yakunashi (no yaku) win (chombo)

   • Can’t win even with complete shape without yaku
   • Check before declaring win
   • Penalty applies

2. Dora is not yaku

   • Cannot win with only dora
   • Always need other yaku
   • Only increases han count

3. Misunderstanding closed yaku

   • Many yaku invalid after calling
   • Riichi, pinfu, tsumo, etc.
   • Need to check beforehand

4. Overlooking kuisagari

   • Some yaku lose han when called
   • Sanshoku, ikkitsuukan, etc.
   • Never drops from 1 han to 0 han

Representative Yaku List

1 Han Yaku

2 Han Yaku

Representative 2 han yaku:
- Sanshoku doujun (1 han when called)
- Ikkitsuukan (1 han when called)
- Chanta (1 han when called)
- Chiitoitsu
- Toitoi
- Sanankou
- Sanshoku doukou
- Sankantsu
- Honroutou
- Shousangen
- Double riichi

3+ Han Yaku

How to Learn Yaku

Learning Order for Beginners

Stage 1: Must memorize
1. Riichi (most basic)
2. Yakuhai (easy to make)
3. Tanyao (high frequency)
4. Tsumo (closed basic)

Stage 2: Commonly used
5. Pinfu (high frequency)
6. Sanshoku doujun (easy to aim for)
7. Ikkitsuukan (clear pattern)
8. Toitoi (simple)

Stage 3: Good to know
9. Honitsu (high scoring)
10. Chiitoitsu (special form)

Yaku Combination Patterns

Yakuman (Highest Yaku)

Representative Yakuman

Relatively common yakuman:
- Kokushi musou (13 different terminals/honors)
- Suuankou (4 concealed triplets)
- Daisangen (3 dragon triplets)

Extremely rare yakuman:
- Chuuren poutou (1112345678999 + 1)
- Tenhou (dealer's starting hand win)
- Chiihou (non-dealer's first draw win)

Yakuman Value

Basic Yaku Building Strategy

Finding Yaku from Hand

Starting hand checkpoints:
1. Honor pairs → Yakuhai aim
2. Many simples → Tanyao aim
3. Many sequences → Pinfu/sanshoku aim
4. Many pairs → Chiitoitsu/toitoi aim
5. One suit bias → Flush aim

Yaku Selection by Situation

Yaku-Related Rules

Combination Rules

1. Simultaneous establishment

   • All qualifying yaku counted
   • Example: Riichi, tsumo, pinfu

2. Higher yaku priority

   • Toitoi and sanankou → sanankou
   • Sanankou and suuankou → suuankou

3. Kuisagari

   • Han decrease when calling
   • Never drops to 0 han

Special Handling

Dora handling:
- Not a yaku
- Always combined with other yaku
- Can add unlimited tiles

Lucky yaku:
- Cannot deliberately aim for
- Ippatsu, haitei, rinshan, etc.
- Bonus-like existence

Conclusion

Yaku is an essential element for winning in mahjong, with at least one required. Beginners should start by firmly memorizing these five: riichi, yakuhai, tanyao, tsumo, and pinfu.

Learning yaku determines your hand direction when looking at starting tiles, enabling efficient hand building. As you improve, aim for compound yaku to target higher scores. Yaku knowledge is the first step to mahjong improvement and an important element for enjoying the game more.