How to play Pentomino Regions
Split the grid into pentominoes — five squares joined side by side — so that two pieces of the same shape never touch, using the letters as clues. Also known as Pentominous, Pentomino division puzzle.
The rules
- Every piece has exactly five squares joined side by side.
- Pieces are named by their shape: F, I, L, N, P, T, U, V, W, X, Y or Z.
- Two pieces of the same shape (turned or flipped counts as the same) may not share a side.
- A letter in a square names the shape of the piece it belongs to.
Playing Pentomino Regions on Puzzle Solvers
- Choose a size and a difficulty, then press New Puzzle.
- Tap a grid line to draw a fence, again to mark it open (✕), again to clear. Drag along lines to do several.
- Each finished five-square piece is coloured and named by its shape; matching shapes that touch turn red.
- Hint places the next piece and explains why it must go there.
Using the Pentomino Regions solver
- Choose the size and type the letters (or press Sample).
- Press Solve and step through each piece: the only one that fits, or the only one left after trying the others.
A worked example
An X piece needs room on all four sides of its centre — so an X letter on an edge square must be one of the X’s arms.
A strip one square wide and five long along the edge can only be an I.
Strategies
- Know the twelve. Learn the shapes: I is a straight line, X a plus sign, U a cup, V a corner of three by three …
- Corners. A corner square can only belong to shapes that fit there.
- Fives. Every closed-off area must have a multiple of five squares.
- Twins. Once you know a piece’s shape, the same shape can’t be placed against it.
- Letters. A letter limits its square to the turns and flips of one shape.
Common mistakes
- Treating a mirrored shape as different — it counts as the same.
- Leaving an area of, say, seven squares that can’t be split into fives.
- Putting two L pieces side by side.
Where it comes from
Pentominoes were named by mathematician Solomon Golomb in 1953; puzzles that divide a grid into them have appeared at world puzzle championships since the 2000s.
Frequently asked questions
Can the same shape appear twice?
Yes — as long as the two pieces don’t share a side.
Do flipped shapes count as the same?
Yes — an L and a mirrored L are both L.
Is there always one answer?
Yes — every puzzle here is checked to have exactly one solution.
How do I solve one from a book?
Open the Pentomino Regions Solver, type the letters and press Solve.
Keep going
- Play Pentomino Regionsa fresh puzzle every time
- Pentomino Regions Solverstep by step, every move explained
- Tetro ShadeShade one piece of four connected squares (an L, I, T or S) in every region…
- Fence RegionsDraw fences along the grid lines to split the grid into regions of the same…
- RectanglesSplit the grid into rectangles so each holds exactly one number, and that…
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