How to Play Nurikabe
Nurikabe is named after a wall-spirit of Japanese folklore that blocks travellers at night. You build the wall; the numbers tell you how much land it must leave standing.
The rules
- Shade squares black to form the wall. Unshaded squares are islands.
- Each number is in an island and gives that island's size in squares. Every island has exactly one number.
- The wall is one connected piece (along sides).
- The wall never contains a 2×2 block of black squares.
Playing on kawu
- Tap a square to make it wall, tap again for a dot (surely island), again to clear. Numbered squares don't change.
- A warning appears if the wall has a 2×2 block; the counter under the grid shows how many wall squares the puzzle needs.
- Undo steps back; Hint fixes a wrong square or marks a correct one.
- Sizes 5×5, 7×7 and 9×9; the daily puzzle is a 7×7 shared by everyone.
Next, read the Nurikabe solving tips.
Frequently asked questions
Can two islands touch?
Not along a side: two white squares touching side by side belong to the same island, which would then have two numbers or be the wrong size. Islands may touch at corners.
Can the wall touch the edge or be a thin line?
Yes to both. The wall may run anywhere; the only shape rules are that it is all connected and never fills a 2×2 block.
Last updated 2026-10-21