🔀 Sliding Puzzle

How to play

Fifteen numbered tiles fill a four by four frame with one space left empty. A tile that sits directly beside the empty space can slide into it, and that is the only move available. Work the tiles round until they read 1 to 15 left to right, top to bottom, with the empty space in the bottom right corner. Every shuffle is checked before it is dealt, so the board you are given can always be solved.

• Click a tile — slides it into the empty space, if the two are directly adjacent. Diagonal neighbours and distant tiles do nothing.
• Shuffle button — deals a new solvable arrangement and resets the move count and the clock.

Scoring

There is no point total. You are measured on Moves, which counts every tile you slide, and Time in seconds. The clock starts on your first move rather than when the board appears, so you can study the arrangement for as long as you like beforehand. Solving the puzzle stops the clock and reports both figures together.

Tips

• Solve the top row first and then leave it alone, then the second row, and finish with the bottom two rows together.
• Think in terms of moving the empty space rather than the tiles. Getting the gap where you need it is most of the work.
• The last two tiles of a row are the awkward part. Place them as a pair by bringing the second one in below the first, then rotating both into place.
• Because the clock only starts on your first click, plan the opening sequence before you touch anything if you are chasing a time.

Frequently asked questions