Jigsaw Sudoku
Irregular jigsaw-shaped regions replace the standard 3×3 boxes
Easy
Jigsaw Sudoku Easy
Medium
Jigsaw Sudoku Medium
Hard
Jigsaw Sudoku Hard
Expert
Jigsaw Sudoku Expert
What is Jigsaw Sudoku?
Jigsaw Sudoku (also called Irregular Sudoku) replaces the nine standard 3×3 boxes with nine irregular jigsaw-shaped regions. Each region still contains nine cells and must still contain every digit 1–9 exactly once. The rows and columns rules remain unchanged. The irregular shapes can create very different solving paths from classic Sudoku.
At a Glance
| Constraint type | Irregular Regions |
| Typical givens | 24–30 |
| Difficulty rating | ★★★☆☆ 3/5 |
| Avg. solve time — Easy | 7 min |
| Avg. solve time — Medium | 16 min |
| Avg. solve time — Hard | 32 min |
| Avg. solve time — Expert | 60 min |
How to Solve Jigsaw Sudoku
| Technique | What it does | Level |
|---|---|---|
| Region Identification First | Identify all 9 irregular regions by their colour coding before solving. Region membership determines the third constraint unit for each cell. | Beginner |
| Region Counting | Each region must contain 1–9. Counting completed rows and columns reveals how many of each digit can still fit in each region. | Intermediate |
| Region–Row/Column Intersection | If a digit within a region is confined to one row or column, eliminate it from the rest of that row or column. | Intermediate |
| Irregular Naked Subsets | Apply naked pairs and triples within each irregular region exactly as you would within standard 3×3 boxes. | Advanced |
Average Solve Times
Easy
7 min
Medium
16 min
Hard
32 min
Expert
60 min
Frequently Asked Questions
Are the regions always the same shape?
No — Jigsaw regions are randomly generated each puzzle. Colours distinguish them.
Do standard 3×3 box techniques apply?
No — the irregular regions replace the standard boxes entirely.