Shikaku
Rectangles left: 0
- Category
- Puzzle
- Players
- 1
- Controls
- Tap
- Grid
- 6 x 6
- Loads
- Instant
Controls
| Tap one corner | Start a rectangle. |
| Tap the opposite corner | Complete it. |
| Tap a finished rectangle | Remove it. |
Next up
| Tap one corner | Start a rectangle. |
| Tap the opposite corner | Complete it. |
| Tap a finished rectangle | Remove it. |
Shikaku asks you to cut a grid into rectangles. Each rectangle must contain exactly one number, and that number must equal the rectangle's area. Every cell ends up inside exactly one rectangle, with none left over and none overlapping.
The pleasure is in how the constraints interlock. A number tells you the area but not the shape, so a six could be one by six, two by three, three by two or six by one — and which one is right depends entirely on what the neighbouring numbers need.
Start with the primes. A number like five or seven can only be a single row or column, which removes almost all the ambiguity and usually pins down a whole strip of the grid.
Look at the ones. A cell marked one is its own rectangle, so it is settled immediately and its neighbours are freed from having to include it.
Work from the edges inward. Rectangles touching a wall have fewer possible shapes than those floating in the middle, so the boundary is where the forced placements live.
Check what a rectangle would swallow. A shape that fits the area but engulfs a second number is illegal, and spotting that quickly saves a lot of trial and error.
The area of the rectangle that contains them, in cells.
No. Exactly one number per rectangle is the central rule.
Never. Every cell belongs to exactly one.
Yes. Each grid is tiled with rectangles first and the numbers are written into them afterwards.
No sign-up, no email, no account. Open the page and Shikaku is ready to play straight away, on a phone or a desktop.