Sliding Block Puzzle
One empty square. Plenty of possibilities.
Slide the tiles into order, or get a little help finding your next move.
Interactive Puzzle
3 × 3 · CLASSICor use arrow keys ↑↓←→ to slide
Solver Controls
Browser-PoweredSolution ready
0 / 0 moves
Both fast and shortest modes find optimal moves on 3×3.
Enter custom numbers
Photo puzzle optional
Algorithm Comparison for This Layout
Compare search algorithms on this exact configuration. Peak states represents search tree frontier size.
| Algorithm | Result | Moves | Time | Explored | Peak states |
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Play the sliding block puzzle
Click a block beside the empty square to slide it into the gap. Keep going until the numbers read from left to right and top to bottom, with the empty square at the lower-right corner. You can also focus a tile and use the arrow keys: each arrow describes the direction a tile moves.
Use Shuffle for a new practice layout. It makes at least twenty legal moves from the goal, so you always have a path back. Reset returns the board to its finished arrangement. Neither action changes your chosen image.
Copying a puzzle from elsewhere? Open Enter your own board and type every number once, using 0 for the gap. Separate numbers with spaces, commas or newlines. Choose the matching board size first.
Sliding blocks or sliding tiles?
These names overlap in everyday searches, but they can describe different games. A sliding tile puzzle uses equal-sized tiles, a fixed grid and one gap. The classic eight puzzle, fifteen puzzle and picture grid are examples.
Other sliding block puzzles use differently sized rectangles in a frame. Klotski and traffic-jam games may ask you to move a target piece to an exit rather than arrange every number in order. Their movement rules require a different solver.
Three ways to make it your own
- 01
Start small
A 3×3 grid gives you room to learn the relationship between a tile and the blank. Try solving the top row, then work on the final two rows together.
- 02
Add a little challenge
Choose 4×4 or 5×5 for a longer practice session. Fast solution helps with large scrambles; Shortest solution searches for the fewest moves and can reach its search limit.
- 03
Make it a picture
Add an image and follow its edges and colors. The small numbers remain a useful reference. The bottom-right image piece is reserved for the gap.
Tips for solving with fewer detours
Choose a target tile before moving. First ask where the gap needs to be, then route it through the unfinished area. Chasing several tiles at once makes it easier to undo your previous work.
Protect completed top rows and solve the last two tiles of a row together. When only two rows remain, finish vertical pairs from left to right. Our How to Solve a Sliding Puzzle guide walks through those setups.
Use the solution as a learning tool
Select Solve my puzzle to check parity and find a route. Choose Fast solution for large scrambles or Shortest solution to minimize moves. A result gives you the tile numbers to move, plus controls to step forward, step back, play or jump to a step. Pause whenever a move surprises you and look at the space it creates.
The search is bounded to keep your browser responsive. If it reaches the time or node limit, the board stays available for play. You can cancel, try Fast solution or return to the Sliding Puzzle Solver for more background on the algorithm.
Frequently asked questions
Which kind of sliding block puzzle is this?
This is the equal-sized tile version: a square or rectangular grid containing numbered blocks and one empty space. Move the blocks into ascending order, leaving the gap in the bottom-right corner. It does not implement differently sized escape blocks.
How do I move a block?
Click or tap a tile next to the empty square. With a board tile focused, use an arrow key to slide a neighboring tile in that direction. Only horizontal and vertical moves into the gap are legal.
Why does Shuffle make a solvable puzzle?
Shuffle begins at the goal and makes at least twenty legal slides, avoiding an immediate reversal. Every slide can be undone, so a route back always exists. These are practice shuffles, not uniformly random samples of every possible board.