Jigsaw Sudoku
Jigsaw Sudoku keeps everything you know about Sudoku, then swaps the nine 3×3 boxes for nine irregular, jigsaw-shaped regions. Each row, each column and each squiggly region must still contain the digits 1–9 exactly once. Also called irregular, squiggly or nonomino Sudoku — play a board below, then read how the shapes change the solve.
How to play Jigsaw Sudoku
- Same digits — every row and every column must contain 1–9 exactly once, just like classic Sudoku.
- Irregular regions — instead of 3×3 boxes, the grid is split into nine jigsaw-shaped regions (outlined in bold); each must also hold 1–9 once.
- No repeats — a digit can’t repeat in any row, column or region.
- Follow the shapes — because regions bend across the grid, scanning works along their irregular edges, not neat 3×3 blocks.
- Play it — tap a cell then a number, ⌫ to clear. Every puzzle has exactly one solution reachable by logic.
What is Jigsaw Sudoku?
Jigsaw Sudoku (also called irregular, squiggly, geometry or nonomino Sudoku) is a Sudoku variant where the nine 3×3 boxes are replaced by nine irregular connected regions of nine cells each. The rules are otherwise identical: fill every row, column and region with 1–9. The bold outlines show the regions — they wind across the grid instead of sitting in tidy blocks.
That one change makes the puzzle feel fresh: the same logic, but your eyes have to follow shapes that bend and interlock.
How the regions change the solve
Because regions are irregular, a digit placed in one cell rules out cells along a winding shape, not a neat square — so scanning and elimination work a little differently. A handy trick carries over from classic Sudoku: the rule of 45. Every region holds 1–9, so its cells always sum to 45. Where a region nearly fills a band of rows or columns, the cell poking in or out is often forced by simple subtraction. Combine that with normal row/column scanning and the irregular shapes start working in your favour.
Easy and hard jigsaw boards
Easy boards give more starting digits so scanning carries you most of the way; hard boards give fewer, so you lean on the region shapes and the rule of 45. Tap New for an endless supply, or switch level above the grid. Every board is generated to have a single solution reachable by pure logic — never guessing.
Jigsaw Sudoku: FAQ
What’s the difference between Sudoku and Jigsaw Sudoku?
The rules are the same — fill 1–9 in every row, column and region — but Jigsaw Sudoku replaces the nine 3×3 boxes with nine irregular, jigsaw-shaped regions outlined on the grid.
Why is it also called irregular or squiggly Sudoku?
They’re all the same puzzle. “Jigsaw”, “irregular”, “squiggly”, “geometry” and “nonomino” Sudoku all refer to Sudoku with irregular regions instead of 3×3 boxes.
Do the same Sudoku techniques work?
Mostly yes — scanning, naked/hidden singles and pairs all carry over. The main twist is that regions bend across the grid, and the rule of 45 (each region sums to 45) becomes especially useful.
Is there always one solution?
Yes. Every board here is generated and checked to have exactly one solution reachable by logic alone, so you never have to guess.
Is it free to play?
Yes — it plays free in your browser on phone, tablet and desktop, with no download and no sign-up. Tap New for a fresh board any time.