How to play pentominoes, with tips
Read from the top and you will be ready to play. It takes about three minutes.
1What is a pentomino?
A pentomino is five squares joined edge to edge. In this puzzle you are given some pieces and fill a frame with all of them, leaving no gaps.
The frame does not show which piece goes where. Turning and flipping the pieces to find where each one fits is the fun of it.
Where does it come from?
The American mathematician Solomon Golomb named pentominoes in 1953, from the Greek for five and the word domino. Even earlier, in 1907, the English puzzle writer Henry Dudeney put a pentomino problem in one of his books.
From what age?
The easy three-piece puzzles suit children from about 5 or 6. The Oni ones, with all twelve pieces, make adults think hard too. With four levels from easy to Oni, there is one for every age.
What does it teach?
You picture pieces turned and flipped in your head, which builds a sense of shape. Counting how many squares are left as you go is the start of thinking about area.
2The twelve pieces
Counting a piece and its turned or flipped forms as one, five squares can be joined in exactly twelve ways. Each looks a little like a letter and goes by it. All are drawn to the same scale.
- F
- Istraight
- L
- N
- P
- T
- U
- V
- Wstairs
- Xcross
- Y
- Z
3Rules
- Use every piece you are givenEach piece once. With one left over, the puzzle is not done.
- No overlaps, nothing outsidePieces never lie on each other or stick out of the frame.
- Turn and flip as you likeThere may be more than one answer. Any way that fills the frame exactly is right.
4Controls
| To | Phone or tablet | Computer |
|---|---|---|
| Put in | Drag a piece into the frame | Drag with the mouse ／ Enter puts it where it fits (the arrows move it) |
| Turn (90°) | Tap a piece in the frame to turn it right ／ the Turn buttons below (either way) | Click a piece ／ Q and E |
| Flip | Flip mirrors the piece you touched last (F on a keyboard) | |
| Pick a piece | Touch it | Tab |
| Undo | Undo takes back one move | Ctrl＋Z |
| Start over | Press Start over twice and every piece goes back where it started | |
Outside the frame, a piece stays wherever you let go of it. Let go over the frame where it does not fit and it goes back to where it lay on the table. A piece never ends up overlapping or sticking out.
"New here?" on the title screen lets you try putting in, turning and flipping in a minute.
5Difficulty and stars
Difficulty (four roads)
The more pieces, the harder.
| Easy | 3–4 pieces, 60 puzzles. A first try |
|---|---|
| Normal | 5–6 pieces, 100 puzzles. A little thought |
| Hard | 8–9 pieces, 100 puzzles. A good long think |
| Oni | All twelve, 50 puzzles. Tough for adults |
Stars (three a stage)
| First | Solve it |
|---|---|
| Second | Solve it without a hint |
| Third | Solve it within the target time (easy 45 s, normal 2 min 30 s, hard 6 min, Oni 15 min) |
Hints
Hint picks one piece and marks where it goes in the frame with a dashed outline; you move it there yourself. If the pieces you have placed can still lead to an answer, it carries on from them. You can use up to half as many hints as the puzzle has pieces (four on an eight-piece puzzle); the number on the button's corner shows how many are left. Only on today's puzzle does each hint add 30 seconds to your time.
6Ways to play
Today's puzzle
- A seven-piece puzzle, new at midnight Japan time. Everyone solves the same one.
- The server keeps the time. Your first solve of the day goes on the ranking.
- Each hint adds 30 seconds to your time.
- Play every day to grow your streak.
Solo
- 310 puzzles on four roads: easy, normal, hard and Oni.
- Start on any road. Along a road, puzzles go from fewer pieces to more. Open are the first one you have not solved and the two after it.
- Free: every easy one, the first 30 normal and hard, and the first 5 Oni (125 in all).
- Past them, one ticket opens the next puzzles along that road (7 normal, 3 hard or 1 Oni). The Lounge Pass opens them all.
- Solved puzzles stay on the list in the colours of your pieces.
Solving earns experience, which raises your level across the whole Puzzle Lounge.
7How to solve
- Start with corners and narrow spotsFew pieces fit in a corner of the frame or in a thin part that sticks out. Settle those before the open middle.
- Keep every gap a multiple of fiveEvery piece is five squares. A shut-in gap of anything but 5, 10, 15… squares can never be filled. Count the gaps each time you place a piece.
A 3-square gap can't be filled Along the edge, 15 squares are left - Keep the X away from cornersThe cross-shaped X can never cover a corner of the frame. Put it next to one and a single square is left in the corner. Finding a place for the X first often helps.
One square left in the corner - Lay the I along an edgeThe straight I tends to cut the frame in two when placed in the middle. Along an edge, what is left stays in one piece.
A 5×5 is left in one piece - When it won't fit, flip itIf the shape is right but facing the wrong way, flip the piece. F, L, N, P, Y and Z can't be turned into their mirror images.
The gap Your N Flipped, it fits - Stuck? Move the first piecesWhen the last piece won't go in, one of the first pieces you placed is usually in the wrong spot. A hint also shows whether the pieces you have placed can still lead to an answer.
8Questions
Can pieces overlap?
No. Pieces never lie on each other or stick out, and together they fill the frame with no gaps.
Is there only one answer?
Not always. Any way that fills the frame exactly is right. The harder the puzzle, the fewer the answers and the harder they are to find.
What happens if I go wrong?
You are not told on the spot. A piece can't be put where it would stick out of the frame or lie on another; it goes back to where it lay on the table. When every piece is in and the frame is full, it is right.
Can I flip a piece?
Yes. Flip mirrors the piece you touched last (F on a keyboard). Six pieces change when flipped: F, L, N, P, Y and Z.
Can I see the answer?
Not all at once. While you play, Hint shows where one piece goes, one at a time. If the pieces you have placed can still lead to an answer, it carries on from them (on today's puzzle each hint adds 30 seconds).
How do I get on today's ranking?
Solve it with a Puzzle Lounge account (a guest one will do), and your first solve of the day goes on it. Each hint adds 30 seconds to your time.
From what age can children play?
The easy three-piece puzzles suit children from about 5 or 6. There are four levels, easy, normal, hard and Oni, so there is one for every age.
How many ways fill the 6×10 rectangle?
With all twelve pieces, 2,339, not counting turns and flips of the whole. A 5×12 has 1,010, a 4×15 has 368, and a 3×20 only 2.
What is the Lounge Pass?
A subscription that takes the ads away in every game and opens everything that would need the Pass or a ticket. Here, all 310 puzzles. Without it, one ticket opens the next puzzles along a road (7 normal, 3 hard or 1 Oni). ¥500 a month or ¥5,000 a year, tax included, with a 7-day free trial the first time. The first 100 founding members pay ¥300 a month or ¥3,000 a year, for as long as they keep it.
Do I need an app?
No. It plays in the browser on phones, tablets and computers.
Is it free? Do I have to sign up?
Free to play, with no sign-up and nothing to download. 125 of the 310 puzzles are free; the rest come with the Lounge Pass or tickets. Today's puzzle and its ranking are free too. Signed in with Google, tickets come free as a daily gift, for solving today's puzzle, and more.