How Slide Fifteen works
Tap a tile that sits next to the empty space to slide it. The puzzle is solved when tiles read 1 to 15 left-to-right, top-to-bottom, with the gap in the bottom-right corner. Shuffle deals a solvable start — every deal is even-permutation legal, so you are never given an impossible board.
Why people stay for another round
The 15-puzzle is older than the web and still addictive because every slide is reversible, yet the solved state feels far away. Counting moves turns a fidget into a personal record.
Tips
- Solve row 1, then row 2, then treat the last two rows as a belt.
- When the last two of a row are swapped, drop them down, rotate, and bring them back.
- Do not panic-shuffle mid-solve. The blank is a tool, not a mess.
Fifteen tiles, one gap. Slide a neighbour into the gap until 1–15 sit in order. Controls: Tap or click a tile beside the gap. Arrow keys slide the tile into the gap.