Lesson 9: Inside vs. Outside Tiles – 5 Simple Rules for Better Hands
Inside vs outside tiles in Mahjong determine how flexible your hand can become and how easily it improves as the game develops. Some tiles give your hand more ways to improve. Others quietly limit your options without you realizing it.
Understanding the difference between inside tiles and outside tiles is one of the fastest ways to improve hand efficiency, reduce stalled hands, and win more consistently.
What Are Inside Tiles?
Inside tiles are the middle-number tiles in a suit: 3–7.
These tiles are powerful because they can connect in multiple directions, giving your hand flexibility as the game develops.
Example: Flexible Inside Shape
This shape can grow in more than one way:
• Into 3–4–5
Or into 4–5–6
Two possible paths means:
- more tiles can help you
- more chances to complete sets
- less pressure to draw one specific tile
This flexibility is what makes inside tiles so valuable, especially early in the hand.
What Are Outside Tiles?
Outside tiles are the edge tiles of a suit: 1–2 and 8–9.
These tiles have fewer ways to connect, which limits how your hand can develop.
Example: Restricted Outside Shape
This shape has only one way to improve:
There is no alternative path.
The same is true for 8–9, which can only become 7–8–9.
Fewer paths means:
- fewer helpful draws
- higher risk of stalling
- less flexibility if the hand needs to change direction
Outside tiles are not “bad,” but they require more careful timing and support.
What This Means in Real Gameplay
Understanding inside vs. outside tiles changes how you evaluate your hand, especially in the early game.
Early in the Hand
• Prioritize keeping inside tiles
• Be cautious holding outside tiles unless they already pair or clearly fit your plan
• Build around shapes that give you multiple improvement paths
Hands built on flexible shapes develop faster and are easier to adjust if the draw changes.
Common Beginner Mistake to Avoid
Many beginners hold outside tiles too long because they feel close to completion. In practice, these tiles often restrict improvement and delay progress. Learning to release outside tiles earlier—unless they clearly fit your plan—keeps your hand flexible and reduces stalled turns.
Key Takeaway
Inside tiles help your hand grow naturally. Outside tiles narrow your options.
By learning to recognize the difference, you’ll make cleaner discard decisions, avoid common efficiency traps, and give yourself more chances to win — without needing perfect draws.
The 5 Simple Rules (Quick Summary)
- Prioritize inside tiles early
Tiles 3–7 create more improvement paths and keep your hand flexible. - Outside tiles need a clear reason to stay
Tiles 1–2 and 8–9 should be supported by a pair or a clear plan, or they often slow your hand down. - Compare shapes, not individual tiles
Choose the shape that offers more ways to improve, not the tile that looks convenient in isolation. - Flexibility beats waiting for the perfect draw
Hands with multiple improvement paths develop more reliably than hands waiting on one specific tile. - Question outside tiles first when adjusting your hand
When your hand stalls or needs to pivot, outside tiles are often the first place to look.
When in doubt, keep the shape that gives your hand more ways to win.
