Fifteen

Tap any tile in the same row or column as the gap to slide it · Keyboard: arrow keys move a tile into the gap

Moves: 0
Time: 0:00
Best: —

Size

The prompt

Make the 15-puzzle in one HTML file in 3×3, 4×4 and 5×5. Shuffle into a random arrangement and use the inversion-count rule to keep only solvable ones. Tapping a tile in the gap's row or column slides the whole line. Animate the slides, tint tiles that are already home, count moves and time, and keep a best score for each size.

Claude wrote this game from a short brief like this one. It was then played, tested on phones and tuned before it went up here.

How to play

Slide tiles into the gap until they read 1, 2, 3… in order, with the gap last.
Tap a tile anywhere in the gap's row or column to slide several at once.
Tiles turn green when they're in their home square.

More like this

Fifteen.