About 15 Puzzle
The 15 Puzzle has been scrambling brains since the 1870s: a frame of numbered tiles, one empty space, and the simple-sounding job of sliding everything back into order. The catch is that each move rearranges your escape routes, and the final rows have humbled generations of solvers.
Choose a gentle 3x3, the classic 4x4, or a sprawling 5x5. Every shuffle is checked to be solvable — no impossible boards, ever — and you can slide whole segments by tapping a tile in line with the gap. Moves and time are tracked as you go, and your best move count is saved for each size. Free in any browser, mouse, keys, or touch.
How to play 15 Puzzle
- Slide tiles into the empty space until the numbers run in order, with the gap ending bottom-right.
- Tap any tile in the same row or column as the gap — the whole segment between them slides in one move.
- Pick your board: 3x3 for a warm-up, the classic 4x4, or 5x5 for a long think.
- Every shuffle is guaranteed solvable, so a way out always exists.
- Finish in as few moves as you can — bests are saved per size.
Controls
- Click or tap a tile next to the gap to slide it — or tap farther along the row or column to slide several tiles at once.
- Arrow keys slide tiles on desktop.
- Use the size selector for 3x3, 4x4, or 5x5, and start a fresh scramble anytime.
Tips & tricks
- Solve the top row first, then the left column, and repeat on the shrinking box — never disturb finished edges.
- Place the last two tiles of each row as a pair: park the corner tile below its home, then rotate both in together.
- The endgame is a small 2x3 region; learn its rotation and the final rows stop being scary.
- Chasing move records? Think in tile cycles rather than one number at a time, and use multi-tile slides.
Frequently asked questions
Is every 15 puzzle shuffle solvable?
Half of all random tile arrangements are mathematically impossible, so we never deal those — every board here is verified solvable before you see it. If a position looks hopeless, a solution still exists.
What is the trick to solving the 15 puzzle?
Work in layers: finish the top row, then the left column, and the puzzle shrinks. Rotate the last two tiles of each row into place as a pair, and the final 2x3 block falls to a simple cycle.
Can I play the 15 puzzle with a keyboard?
Yes — arrow keys slide tiles into the gap on desktop. On phones and tablets, tap tiles directly; tapping farther down a row or column slides the whole segment in one move.
