Sliding Puzzle

About the Sliding Puzzle

The sliding puzzle — often called the 15-puzzle in its 4×4 form — is a classic tile-sliding brain teaser invented in the 1870s. Numbered tiles are scrambled inside a frame with one empty space, and you slide tiles into that gap one at a time until they're back in order. Every board this game deals is guaranteed to be solvable, so it's always a question of technique, not luck. Solve the top row and left column first, then work down into the smaller remaining square.

How to play

• Tap any tile next to the empty space to slide it in.
• Arrange the numbers 1…N in order with the blank in the bottom-right.
• Try to solve it in as few moves and as little time as possible.
• Switch between a gentle 3×3 and the classic 4×4 board.