Sudoku 18x18 num: 535 (Level: hard)
E
C
8
6
3
I
H
I
4
7
C
9
5
3
2
3
B
I
4
H
F
D
8
3
I
B
2
I
4
7
8
9
8
3
B
6
H
1
4
G
4
F
5
2
B
8
9
6
I
B
D
1
6
I
B
7
G
D
E
F
4
6
H
3
B
H
D
G
8
A
B
2
1
D
G
F
4
E
9
F
5
A
2
7
B
3
8
1
5
9
E
C
A
B
D
3
2
B
D
1
I
7
4
9
I
B
7
H
E
5
C
6
2
3
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HID147GCF9E5863B2A
A823B6I47DH1GF5C9E
7H4DG1E85CF9A32IB6
6AB2I3HG147DE598CF
FEC985AI3B62H1DG47
17G4EDFA985C62BHI3
5F8CA96H2I3B7D4EG1
36IBH27EDG14F9CA85
D1EGF456CA983BI7H2
95A86C37BH2I14GFED
23HI7B1F4EDG5C86A9
B27H1ID5GF4E98A36C
4DFE5G9386CA2IH17B
C96A3821I7BHDGE5F4
G45F9EC2A386BH7D1I
8C362ABDH1I74EF95G
IB17DH49E5GFCA6238
Sudoku 18x18
Sudoku 18x18 is a bold expansion of the classic puzzle, stretching the challenge across a grid of 18 rows and 18 columns. The board is organized into 18 regions of 3x6 cells, and, as always, each number must appear only once in every row, column, and region. Instead of the usual nine symbols, you'll work with the numbers 1 through 18, which makes the puzzle broader and more dynamic. The larger variety of digits creates more possibilities but also more patterns to discover, rewarding players who enjoy patience, observation, and logical deduction. It's not about racing to the end but about carefully building the solution piece by piece.
Every puzzle begins with a set of starting numbers scattered across the grid. These initial clues provide the foundation for your reasoning, helping you eliminate candidates and trace the flow of logic throughout the puzzle. There is always a single unique solution, reached without guessing, making every step meaningful. This 18x18 version is ideal for players who already feel comfortable with formats like 12x12 or 16x16 and are ready to explore something even more expansive. It offers a fresh mental workout that improves concentration, strengthens analytical skills, and builds persistence. Solving an 18x18 Sudoku is like assembling a giant mosaic-each correct placement contributes to the beauty of the completed board.