The picture is cut into a square grid with one tile missing. Slide tiles into the gap until the scene is back together. Boards run from a quick 3×3 to a long 6×6.
How to play
Tap a tile next to the gap, or swipe it toward the gap, and it slides in. Tap a tile further along the same row or column and the whole line moves at once. On a keyboard, the arrow keys move the tile next to the gap.
Put every tile back in its place. The gap belongs in the bottom-right corner; when the last tile arrives, the missing piece of the picture fades in.
The # button shows numbers on the tiles, which helps where the picture is plain. Hint highlights a good next tile, Undo steps back through your moves, and Show picture opens a preview of the finished scene.
Every deal can be solved. Exactly half of all possible arrangements of a sliding puzzle are impossible, and the game only ever deals from the solvable half.
Strategy that works
Solve the top row first, then the second, and never break a finished row. The board shrinks as you go: a 5×5 becomes a 4×5, then a 3×5, and so on.
The last tile of each row is the tricky one. Place the second-to-last tile in the corner position first, put the last tile directly below it, then slide the pair into place together. Trying to insert the last tile directly usually means breaking the row.
When only two rows remain, change direction and work column by column from the left, using the same pairing trick. The final 2×2 corner then turns itself into place in a few moves.
Plain areas such as night sky or snow are the slow part. Turn the numbers on for those rows and turn them off again once the more detailed part of the picture starts — it is more satisfying to finish by eye.
Bigger boards are not just longer, they demand more planning. Move up one size at a time: 3×3 to learn the movement, 4×4 for the classic puzzle, 5×5 and 6×6 for patience.
Questions and answers
Is every sliding puzzle solvable?
Yes. Half of all random arrangements cannot be solved, so the game checks the arrangement before dealing it and only gives you solvable ones.
Where does the gap have to end?
In the bottom-right corner. The puzzle counts as solved when every tile is in its place and the gap is there.
How does the hint work?
On 3×3 the hint follows a shortest solution. On larger boards it searches for a good move within a limited budget; if a position is too hard to search, it switches the numbers on and points at a tile that is out of place.
Can I move several tiles at once?
Yes. Tap a tile in the same row or column as the gap, further away, and the whole line between it and the gap slides together.
Is my game saved?
Yes, in this browser, including your undo history. Each picture keeps its own saves.