Minkan (Open Kan) - Making a Quad from Opponent's Discard

What is Minkan?

Minkan (open kan) is a basic mahjong action where you form a 4-tile meld using an opponent’s discarded tile. When you have 3 identical tiles and an opponent discards the 4th, declare “Kan!” to complete it.

After minkan, you draw a rinshan tile and a new kandora is revealed. Like pon, it’s a type of call that breaks your closed hand, but offers chances for higher scoring and dora increases.

Requirements

Minkan Procedure

1. Opponent discards target tile
   ↓
2. Declare "Kan!"
   ↓
3. Expose 3 tiles from hand (1 sideways)
   ↓
4. Draw 1 rinshan tile
   ↓
5. Discard 1 tile
   ↓
6. Kandora revealed (immediately)

Display Method

Showing who discarded:

From kamicha: [5][5][5][→5]
From toimen: [5][5][→5][5]
From shimocha: [→5][5][5][5]

(→ indicates sideways tile)

Minkan Benefits

1. Kandora increase

   • New dora indicator
   • Score boost chance

2. Rinshan tile

   • Extra draw
   • Rinshan kaihou possible

3. Sankantsu

   • Path to 2 han yaku
   • High-scoring potential

Minkan Drawbacks

1. Chankan risk

   • Can be ronned during kan
   • Give away winning tile

2. Others get dora too

   • Kandora helps everyone
   • Could backfire

3. Hand exposed

   • Information leaked
   • Waits more readable

When to Kan

Good Situations

Bad Situations

Minkan vs Ankan vs Kakan

Selection Criteria

• 4 in hand → Ankan
• After pon → Kakan
• Opponent discards → Minkan

Chankan Risk

What is Chankan

You: Have three 5m
Opponent discards 5m
↓
"Kan!" declaration
↓
Another opponent: "Ron!"
→ Chankan (kan interrupted)

Risk Reduction

• Don’t kan dangerous tiles
• Careful when many tenpai
• Extra caution late game

Strategic Points

Early Game Kan

• Kan if hand is bad
• Active if dora
• Watch for tenpai break

Mid Game Kan

• Score boost purpose
• Read opponent situation
• Kandora expected value

Late Game Kan

• Don’t kan if tenpai
• Defense priority
• High chankan risk

Common Mistakes

1. Ankan confusion

   • Minkan: Uses opponent’s tile
   • Ankan: Own 4 tiles

2. Display errors

   • 1 tile sideways
   • Shows who discarded

3. Rinshan draw

   • Not from regular wall
   • Draw from dead wall

4. Kandora timing

   • Revealed after discard
   • Not before rinshan draw

Related Terms

• Ankan: Closed kan with own tiles
• Kakan: Add 4th to pon
• Rinshan-hai: Tile after kan
• Kandora: Dora from kan
• Rinshan Kaihou: Win on rinshan

Summary

Minkan forms a 4-tile meld using an opponent’s discard. With 3 identical tiles, declare “Kan!” when the 4th is discarded. This gives you a rinshan draw and reveals kandora for scoring chances, but carries chankan risk and gives dora to opponents too. Beginners should remember “opponent’s tile = minkan” and try it when holding dora or seeking score boosts. It’s a deep strategic action requiring good judgment.