Slide Fifteen

Slide a solvable 4×4 number puzzle into perfect order, with unlimited undo and fresh legal scrambles.

How to play Slide Fifteen

Arrange tiles 1–15 in row order, leaving the bottom-right space empty. Cyan outlines mark movable tiles; green tiles are in the right place. Every slide, including undo, adds one move. Fewer moves is better.

Tap a tile beside the empty space. Arrow keys move the empty space. U or Backspace undoes; S or the Scramble button starts a fresh puzzle. Touch users can tap both buttons.

Inspired by Numpuz. An independent, original browser adaptation.