Easy Irregular Sudoku

Jigsaw-shaped regions replace the 3×3 boxes. Rows, columns, and irregular regions must each hold 1–9. No download, no login.

Easy Medium Hard Expert

New to Irregular Sudoku? Jigsaw-shaped coloured regions replace the standard boxes. Rows, columns, and regions must each hold 1–9 once. Start here.

2
7
1
5
5
3
8
2
7
4
9
8
6
5
3
7
4
8
1
7
6
4
8
9
2
9
6
3
1
1
3
5
8
4
6
6
4
3
Mistakes
0/3
Score
-
Time
00:00
Try Medium Irregular Sudoku →
Progress0%

What is Jigsaw Sudoku?

Difficulty
★★★☆☆
3/5
Constraint Type
Irregular Regions
Typical Givens
24–30
Avg. Solve (Easy)
7 min

Solving Techniques for Easy Level

Technique Description 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

Ready to go deeper? Try Medium Jigsaw Sudoku to unlock Intermediate techniques.

Techniques to Master at Easy

  • Last Free Cell technique — Snaking regions complete at unexpected moments — count the cells of each colour, not 3×3 blocks, and the last free cell of a region is often sitting in plain sight.
  • Last Remaining Cell technique — A jigsaw region spanning five rows blocks its digits across all five at once, so a digit's only legal cell in a neighbouring region shows up faster than in box Sudoku.

Average Solve Time by Difficulty

Easy
7 min
Medium
16 min
Hard
32 min
Expert
60 min
Want a full walkthrough of rules, strategies, and solving steps? How to Play Jigsaw Sudoku →

Related Variants

Irregular Diagonal Sudoku

Your jigsaw region-reading skills plus two diagonal houses — the natural step up in constraint density.

Chaos Construction

Jigsaw solving where the regions themselves are hidden — you deduce the borders while you place the digits.

Samurai Sudoku

Scales the geometry challenge a different way: five overlapping grids whose shared boxes pass information between them.

Frequently Asked Questions — Easy Irregular Sudoku

What is Irregular Sudoku?
Irregular Sudoku (also called Jigsaw Sudoku) replaces the standard 3×3 boxes with nine irregularly shaped regions of nine cells each. Every row, every column, and every coloured jigsaw region must contain the digits 1–9 exactly once.
How do the coloured regions work in Irregular Sudoku?
Each colour on the board marks one of nine regions. Every region contains exactly nine cells arranged in a non-rectangular shape. You must place the digits 1–9 in each region, just like you would in a standard 3×3 box — no repeats allowed within the same colour.
How is Irregular Sudoku different from standard Sudoku?
Standard Sudoku uses fixed 3×3 square boxes. Irregular Sudoku swaps those boxes for jigsaw-shaped regions that can span multiple rows and columns. The row and column rules stay the same, but the region shapes change the solving logic entirely.
What is the best way to start an easy Irregular Sudoku?
Start by scanning rows and columns for digits that appear many times — once you've placed a digit in most rows and columns, the remaining cells narrow down quickly. Then look at each region and see which digits are still missing. Easy puzzles have enough givens that you rarely need pencil marks.
Do I need to use pencil marks on easy Irregular Sudoku?
Usually not on easy. Most easy Jigsaw Sudoku puzzles can be solved by scanning rows, columns, and regions for singles — cells where only one digit fits. If you get stuck, briefly noting one or two candidates in a tricky cell is enough to break the deadlock.

More questions? See the full Irregular Sudoku guide.