The single rule that decides whether you can select a tile is simple, but new players misread it constantly. Get it wrong and the game feels broken; get it right and the whole board opens up. This guide explains the playable rule, how to read a stack, and the most common mistakes to avoid. For the broader rules, see our Mahjong Solitaire Rules guide.
The Playable Rule
A tile is playable only when both of these are true: (1) no tile sits directly on top of it, and (2) at least one long edge, left or right, is free (no tile touching that side). If either condition fails, the tile is locked and you cannot select it until the blocking tiles are removed.
Reading a Stack
On this site, playable tiles glow or lighten when you hover over them. If a tile stays dim, it is blocked. Train your eye to scan in this order: top of the stack first (to find unburied tiles), then the left and right edges (to find free long edges). With a few games of practice, you will read the board at a glance.
Common Mistakes
- Ignoring the stack height and wasting time clicking buried tiles.
- Matching edge pairs too early, locking the row behind them.
- Forgetting that a tile with both long edges covered is unplayable, even with nothing on top.
Frequently Asked Questions
Why can I not select this tile?
Either a tile is on top of it, or both its left and right long edges are blocked. Clear the blockers first.
How do I tell if a tile is playable?
Hover over it. Playable tiles highlight; unplayable tiles stay dim. You can also use a Hint, which always points to a playable pair.
Want to test your eye? Open the Classic layout – its flat shape makes the playable rule easy to study.