Medium 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

Irregular Sudoku at medium difficulty. The jigsaw regions cross multiple rows and columns — region logic combines with standard scanning for satisfying multi-step deductions.

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

What is Jigsaw Sudoku?

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

Solving Techniques for Medium 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
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

Master these, then take on Hard Jigsaw Sudoku to learn Advanced techniques.

Techniques to Master at Medium

  • Hidden Singles technique — Scan each jigsaw shape as its own house: regions that snake across many rows and columns concentrate eliminations, making hidden singles the workhorse of medium jigsaw grids.
  • Obvious Pairs technique — A pair inside a long, thin region eliminates along every row and column the region touches — far more reach than a pair confined to a 3×3 box.

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 — Medium Irregular Sudoku

What techniques help most on medium Irregular Sudoku?
Medium puzzles require combining row/column scanning with region logic. Look for hidden singles — cells where a digit can only go in one place within a region even if multiple candidates seem possible. Also watch for naked pairs within a region, which eliminate candidates from other cells in the same region.
Why does the irregular shape make medium puzzles harder than standard Sudoku?
Irregular regions cross row and column boundaries in unpredictable ways. A region may span three different rows, so eliminating a digit from one cell of the region has cascading effects across those rows. Tracking this takes more effort than the aligned 3×3 boxes in standard Sudoku.
How do I find hidden singles in Irregular Sudoku?
For each region, take one digit at a time and ask: in how many cells of this region can this digit legally go? If only one cell is possible — because the digit already appears in that cell's row, column, or another region — that is a hidden single. Place the digit there immediately.
How long does a medium Irregular Sudoku take to solve?
Most players finish medium Jigsaw Sudoku in 15–25 minutes. If you're new to irregular regions, add a few minutes while you get used to reading the region shapes. The puzzle is designed to be solvable with only basic and intermediate logic — no advanced techniques needed.
Can I use standard Sudoku techniques on Irregular Sudoku?
Yes — all standard Sudoku techniques (singles, pairs, triples, pointing pairs) apply directly. The only adjustment is replacing '3×3 box' with 'region' in every rule. Pointing pairs still work when a digit within a region is confined to a single row or column, eliminating it from the rest of that row or column.

More questions? See the full Irregular Sudoku guide.