Pentomino

How to play pentomino puzzles

• A pentomino is a shape made of five squares joined edge to edge. There are exactly 12 of them, named after the letters they look like: F, I, L, N, P, T, U, V, W, X, Y and Z.
• Fill the board completely with the pieces in the tray. You can turn the pieces and flip them over, but they can’t overlap.
• Drag a piece onto the board. You can also tap a piece to pick it, then tap a square on the board to put it there.
• Tap a picked piece again, or press “Rotate”, to turn it. “Flip” turns it over. On a computer, press R to rotate and F to flip, even while you drag.
• To take a piece off the board, drag it back to the tray, or tap its faded spot in the tray. Ctrl+Z (or “Undo”) takes back your last move.
• Stuck? “Hint” places one piece for you that leads to a solution. If a piece on the board makes the puzzle impossible, that piece is marked instead.

Levels and boards

• Easy puzzles use 4 pieces to fill a 4×5 box, Medium uses 6 pieces (5×6) and Hard uses 8 (5×8). Each time you get a different set of pieces, and every set has at least one solution.
• Expert uses all 12 pieces (60 squares). Pick the board from the menu at the top left: the classic 6×10 rectangle, 5×12, 4×15, the very hard 3×20, or an 8×8 square with a 2×2 hole in the middle.
• On Expert boards, the game keeps count of the different solutions you’ve found.

Solutions that are just the whole board turned or flipped over count as one. We checked every count with our own solver.

Example solutions

Pick a board below to reveal one of its solutions. Try solving it yourself first!

Tips for solving pentominoes

• Watch out for gaps. Every closed-off empty area needs a multiple of 5 squares. If you wall off 3 or 7 squares, no pieces can ever fill them.
• Fill the corners and edges first. Pieces with a square corner, like V, L, P, T and U, fit corners well.
• Find a place for the X early. It can never fill a corner, and it can’t sit right next to one either, because the corner square would be trapped.
• The long I piece lies along an edge of the board in 2,314 of the 2,339 solutions to 6×10.

Daily puzzles

• Each level has its own daily puzzle. Everyone gets the same puzzles, and new ones arrive once a day at midnight Japan time (15:00 UTC).
• The Expert daily puzzle is an 8×8 board with 4 squares blocked off, different every day.
• Solve the daily puzzle every day to build a streak.

About pentominoes

The mathematician Solomon W. Golomb coined the name “polyomino” in 1953, and Martin Gardner’s columns in Scientific American made pentomino puzzles famous. In 1958 Dana Scott used a computer to find all 65 ways to fill the 8×8 board with a hole in the middle, and in 1960 C. B. and Jenifer Haselgrove found the 2,339 solutions to the 6×10 rectangle.

Your puzzle is saved as you play, so you can close the page and pick up where you left off.