Medium Irregular Diagonal Sudoku

Ready to sharpen your skills? Medium Irregular Diagonal Sudoku puzzles introduce interactions between the variant constraint and classic Sudoku techniques. You'll need to combine both skill sets to progress.

▶ Play Medium Irregular Diagonal Sudoku All Irregular Diagonal Sudoku Difficulties

What to expect at Medium level

Medium Irregular Diagonal Sudoku puzzles require you to combine the variant constraint with standard Sudoku deduction - Naked pairs, hidden singles, and unit scans. The constraint is more tightly woven into the grid, so you'll need to think a few steps ahead.

Best suited for players comfortable with Easy Irregular Diagonal Sudoku who want to build their pattern recognition.

Difficulty overview

LevelCluesTechniques neededAvg. time
Easy ManyBasic elimination5–10 min
Medium ModerateSingles, pairs10–20 min
Hard FewAdvanced logic20–40 min
Expert MinimalFull mastery40+ min

About Irregular Diagonal Sudoku

Difficulty
★★★★☆
4/5
Constraint Type
Combined: Irregular + Diagonal
Typical Givens
22–30
Avg. Solve (Medium)
18 min

Irregular Diagonal Sudoku combines two variant types: the irregular jigsaw regions of Jigsaw Sudoku and the diagonal constraints of Diagonal Sudoku. Both main diagonals and all irregular regions must contain 1–9. The combination creates highly constrained puzzles with unique solving logic.

Solving Techniques for Medium Level

Technique Description Level
Map All 29 Units First You have 9 rows + 9 columns + 9 irregular regions + 2 diagonals = 29 constraint units. Identify all irregular regions and both diagonals before starting. Beginner
Diagonal–Region Intersection Cells on a diagonal that also sit in the same irregular region create a powerful two-unit intersection — use both constraints simultaneously. Intermediate
Diagonal Pointing Pairs If a digit on a diagonal is confined to one irregular region, eliminate it from all other cells of that region. Intermediate

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

Average Solve Time by Difficulty

Easy
8 min
Medium
18 min
Hard
35 min
Expert
65 min

Frequently Asked Questions

Which diagonals are constrained?
Both main diagonals: top-left to bottom-right and top-right to bottom-left.
Are the regions always the same shape?
No — irregular regions are randomly generated per puzzle with different boundaries each time.
How many constraint units does the centre cell belong to?
The centre cell (row 5, col 5) is on both diagonals, plus its row, column, and irregular region — 5 units total.