Sliding Puzzle

The Sliding Puzzle, also known as the 15 Puzzle, Gem Puzzle, or Boss Puzzle, is one of the most famous mechanical puzzles in history. Invented in the 1870s, it consists of numbered tiles arranged in a square grid with one empty space. Players slide tiles into the empty space to rearrange them into numerical order. The classic version uses a 4x4 grid with tiles numbered 1 through 15. The puzzle became a worldwide craze in the 1880s, with newspapers offering cash prizes for solutions. It was later proven that exactly half of all possible starting positions are solvable, making it one of the earliest examples of a mathematically analyzed puzzle. The Sliding Puzzle remains a beloved test of spatial reasoning, planning, and patience.

1. Tiles are arranged randomly in a grid with one empty space.
2. Click or tap a tile adjacent to the empty space to slide it into that space.
3. Only tiles directly next to the empty space (up, down, left, right) can be moved.
4. Continue sliding tiles to arrange them in numerical order from left to right, top to bottom.
5. The empty space should end up in the bottom-right corner when the puzzle is solved.
6. Try to solve the puzzle in as few moves as possible.

• Only tiles adjacent to the empty space can be moved
• Tiles slide into the empty space (they cannot jump over other tiles)
• The goal is to arrange tiles in sequential order (1, 2, 3, ... from top-left)
• The empty space belongs in the bottom-right corner
• Only horizontal and vertical slides are allowed (no diagonal moves)
• Every starting configuration in our game is guaranteed to be solvable

• Solve the puzzle row by row from top to bottom. Lock the first row in place, then the second, and work downward.
• When placing tiles in the top row, first position tile 1 in the top-left, then tile 2 next to it, and continue across.
• For the last two tiles in each row, use a rotation technique: position both tiles near their target, then rotate them into place simultaneously.
• Once the top rows are solved, work on the remaining rows using the same technique in a smaller space.
• The final 2x3 or 2x2 section requires careful cycling of tiles. Practice this subproblem separately to build confidence.
• Count your moves and try to reduce them. Efficient solutions require planning several moves ahead.

• 3x3 (8 Puzzle): A smaller version with tiles 1 through 8. Perfect for learning the solving technique before tackling larger puzzles.
• 4x4 (15 Puzzle): The classic version with tiles 1 through 15. The standard challenge that has captivated puzzle lovers for over a century.
• 5x5 (24 Puzzle): A larger version with tiles 1 through 24. Significantly more challenging and time-consuming than the classic 4x4.
• 6x6 (35 Puzzle): An expert-level puzzle with tiles 1 through 35. Demands advanced solving techniques and significant patience.
• 7x7 (48 Puzzle): The ultimate sliding challenge with tiles 1 through 48. Only for the most dedicated puzzle solvers.
• 9x9 (80 Puzzle): An extreme puzzle with tiles 1 through 80. A marathon of spatial reasoning and endurance.
• 10x10 (99 Puzzle): The largest sliding puzzle available with tiles 1 through 99. The ultimate test of patience and methodical planning.

• One of the oldest and most iconic puzzles in history
• Develops spatial reasoning and planning skills
• Deeply satisfying moment when tiles click into place
• Scalable difficulty from easy 3x3 to colossal 10x10
• Always solvable with the right technique and patience

Play the Sliding Puzzle for free in your browser. Choose from 3x3, 4x4, 5x5, 6x6, 7x7, 9x9, or 10x10 grid sizes. Features smooth tile animations and move counting. No downloads required. Works on all devices.

The Sliding Puzzle is a timeless test of spatial thinking and methodical problem solving. From the easy 3x3 to the colossal 10x10, every puzzle rewards patience and planning. Slide your first tile and experience the puzzle that captivated the world over a century ago.