🔲 Sliding Puzzle Guide

Overview

The Sliding Puzzle (also called the 15-Puzzle in its 4×4 form) is a classic single-player puzzle where numbered tiles must be arranged in order by sliding them into an empty space. It was invented in the 1870s and has been a staple of puzzle collections ever since.

How to Play

1. Click a tile adjacent to the empty space to slide it into the gap.
2. Only tiles directly next to the empty space (horizontally or vertically) can move.
3. Arrange all tiles in numerical order, left to right, top to bottom.
4. The empty space should end up in the bottom-right corner.
5. Your score is the number of moves taken — fewer is better.

Rules

• Only one tile moves per click.
• Tiles can only slide into the empty adjacent space.
• Diagonal moves are not allowed.
• Three grid sizes: 3×3 (8 tiles), 4×4 (15 tiles), 5×5 (24 tiles).

Strategy Tips

• Solve top row first: Lock the first row into place, then never disturb it.
• Work left to right: After the top row, solve column by column within each row.
• Corner technique: For the last two tiles in a row, position them together before rotating into place.
• Don't undo progress: Plan 3-4 moves ahead to avoid displacing solved tiles.
• Practice the 3×3: Master the small grid before tackling 4×4 or 5×5.

Difficulty Levels

• 3×3: 8 tiles — quick and approachable, solvable in under 30 moves.
• 4×4: 15 tiles — the classic challenge, expert solvers finish in ~50 moves.
• 5×5: 24 tiles — seriously difficult, requires careful planning.