Goal

Arrange all numbered tiles in order from 1 to the last number, with the empty space in the bottom-right corner.

Controls

• Click or tap any tile adjacent to the empty space to slide it in
• Only tiles directly above, below, left, or right of the empty space can move

Scoring

• Your score is the number of moves used — fewer is better!
• A timer tracks how long you take
• Your best (lowest move count) is saved per difficulty

Difficulty

• Easy (3×3) — 8 tiles, simpler puzzle
• Medium (4×4) — 15 tiles, the classic challenge

Is every shuffle solvable?

Yes! The game uses a mathematical solvability check and keeps reshuffling until a valid (solvable) board is generated. You will never get a puzzle that is impossible to solve.

Is my best score saved?

Yes — your best move count is saved separately for Easy and Medium in your browser's local storage. It persists between sessions on the same device.

Does switching difficulty reset my best?

No — each difficulty has its own independent best score stored separately.

Why can some tiles not move?

Only tiles that are directly adjacent (horizontally or vertically) to the empty space can slide. Diagonal moves are not allowed.