Shift
Also known as Sliding Puzzle, Number Slider, 15 Puzzle, Fifteen Puzzle, Slide Puzzle, Sliding Tiles and Gem Puzzle
The tile puzzle from every childhood pocket: slide the numbered tiles around the one empty space until they are back in order. Every board is shuffled using legal moves only, so every one of them can be solved.
How it works
- Arrange the numbered tiles from left to right, leaving the final space empty.
- Tap a tile directly beside the blank to slide it into the open space.
- Tiles cannot jump, move diagonally, or swap with each other.
- Every shuffle is made from legal moves, so every board is solvable.
Good if you want…
- Rules you can explain in one sentence
- No reading required
- A quick go at something familiar
How to solve Shift
Solve it one row at a time
The reliable way to solve any sliding puzzle is to shrink it. Put the top row in order and never touch it again. Then do the left-hand column, and never touch that again either. What is left is a smaller puzzle of exactly the same kind, and you repeat until only a two-by-two corner remains, which you can simply rotate into place.
The last two tiles in a row
Placing the first few tiles of a row is easy. The last two are the famous difficulty: putting one in place knocks the other out. The trick is to place them as a pair. Park the final tile of the row directly below where it belongs, bring the second-to-last tile into the last position, then walk the gap round and slide the pair home together: the second-to-last tile across into its own place, and the last tile up into the corner behind it. It feels like going backwards the first time, and after that it is routine.
Move the gap, not the tile
It helps to think of the empty space as the thing you are moving. To bring a tile left, walk the gap round to its left side and slide it across. Planning the gap's route around tiles you have already placed is what stops you undoing your own work.
Common mistakes
- Placing tiles in the finished rows out of order. Solve strictly row by row; disturbing a finished row costs far more moves than it saves.
- Trying to fix the last two tiles of a row one at a time. Place them together.
Where Shift comes from
The 15 Puzzle swept the United States in 1880 and is usually credited to Noyes Chapman, a postmaster in New York State. Around the same time, mathematicians proved that exactly half of all possible arrangements can never be solved — which is why the most famous challenge of the craze, swapping just the 14 and 15, had no answer.
Shift questions
Is every board solvable?
Yes. Every board in Winters Puzzles is shuffled with legal moves only, so it can always be put back.
Can I lift a tile out?
No. Tiles can only slide into the empty space next to them — they cannot jump, move diagonally or swap.
Shift in Winters Puzzles
Shift is one of 40 puzzles in Winters Puzzles, so it sits alongside Tessera, Ripple, Flow and everything else in the app rather than being a download of its own. It counts towards your stats and streak like any other puzzle. It is not one of the puzzle types included in Pip’s dailies.
Play Shift.
Free on iPhone and iPad, with 39 other puzzles alongside it. Or play it in your browser — no download, nothing to sign up for.
