What is Toitoi? All Triplets Yaku Explained for Beginners

What is Toitoi?

Toitoi (対々和, Toitoihou) is a 2-han yaku in mahjong where all 4 sets are triplets (same tile x3). Called “toitoi” for short, it’s an aggressive yaku that’s easy to aim for when your starting hand has many pairs.

Using no sequences and collecting 3 of the same tile makes it easy to understand. Since it works when open, beginners can easily aim for this yaku.

Detailed Explanation of Toitoi

Conditions for Completion

Toitoi Examples

Closed toitoi:

111m 333m 666p 999s CC

Open toitoi:

Hand: 111m EEE WW
Pon: 555p SSS

Difference from Chiitoitsu

Usage Examples

Real Game Situations

Example 1: Starting hand judgment

"5 pairs! Toitoi or chiitoitsu?"
"Toitoi lets me call so it's faster"

Example 2: Pon decisions

"Pon! Toitoi confirmed"
"One more pon and I'm tenpai"

Example 3: Winning joy

"Toitoi sanankou!"
"Toitoi dora 3 for mangan!"

How to Make Toitoi

Basic Strategy

1. Aim with many pairs

   • 4+ pairs is ideal
   • 3 pairs still possible

2. Pon aggressively

   • Advance toward tenpai
   • Confirms the yaku

3. Cut isolated tiles early

   • Don’t make sequences
   • Keep tiles that might pair up

Example Progression

Early: Check pairs

Starting: 11m 33m 55p EE S WW 678s CC
→ 5 pairs, toitoi promising

Mid: Pon to shape

Pon East → 3 more triplets needed
Break sequence 678s and cut

Late: Wait form

Pattern 1: Shanpon wait (22m 55p for 2m or 5p)
Pattern 2: Tanki wait (4 triplets done, pair tanki)

Related Terms

• Koutsu: Same tile x3
• Toitsu: Same tile x2
• Sanankou: Often combines
• Suuankou: Ultimate toitoi
• Pon: Calling for triplets

Common Mistakes and Points to Note

Points Beginners Often Mistake

1. Sequence mixed in

   • 123m means no toitoi
   • All must be triplets

2. Confusion with chiitoitsu

   • Form is different but aim is similar
   • Big difference: calling allowed or not

3. Quads count as triplets

   • Kan still allows toitoi
   • 4-tile use OK

4. Sanankou combination condition

   • Ron: ron tile’s triplet is minkou
   • Shanpon wait needs attention

Yakus that Combine with Toitoi

Often Combined

Doesn’t Combine

• Pinfu: Has triplets, can’t
• Iipeikou/Ryanpeikou: Needs sequences
• Sanshoku/Ikkitsuukan: Needs sequences
• Chiitoitsu: Different form

Strategic Points

When to Aim for Toitoi

1. Many pairs in starting hand

   • 4+ pairs is promising
   • Honor pairs even better

2. Want quick win

   • Pon accelerates
   • 2 han confirmed, has score

3. Pressure opponents

   • Hand advances with pon
   • Shows high score potential

Pros and Cons

Pros:

• Can make with calls (speed)
• 2 han confirmed (has score)
• High combos with sanankou
• Dora pairs easy to use

Cons:

• Triplets are hard to make (~11% chance)
• Calling reduces defense
• Wait is readable
• Can get stuck

Practical Tips

Pon Decisions

1. Should pon aggressively

   • Honor tiles (become yakuhai)
   • Dora
   • Early round tiles

2. Consider not ponning

   • Can aim for sanankou
   • Better alternative hand
   • Need defense

Reading Toitoi

Signs opponent might have toitoi:

• Many pair discards
• 2+ pons
• Holding honors

Defense:

• Hold tiles that might pair
• Prioritize safe tiles
• Watch for shanpon waits

Conclusion

Toitoi is an easy-to-understand 2-han yaku where all sets are triplets. Easy to aim for with many pairs in starting hand, and since it works when open, you can attack aggressively. Beginners should learn the basics “all 4 triplets” and “calling OK,” then when you see many pairs, judge between chiitoitsu and toitoi. Combined with sanankou for even higher scores - an attractive yaku.