Sudoku 18x18 num: 551 (Level: hard)
F
5
E
9
8
G
2
3
F
6
9
2
3
H
5
C
E
F
D
8
1
H
G
H
I
9
3
F
A
E
B
1
5
9
D
A
3
1
C
6
9
H
1
I
4
G
H
2
E
C
4
I
B
9
6
7
2
H
2
7
G
5
E
D
C
8
B
I
8
B
H
C
D
5
E
8
9
7
D
9
4
8
G
F
E
A
3
G
6
B
1
I
9
I
1
H
A
E
C
B
E
1
9
2
A
3
D
D
A
B
4
I
8
7
DAF3H25C4BE8I9671G
B48CE5I9G71623FDHA
7G691I23ADHF5C8BE4
AFED23CB845197HGI6
G6H7I93DFA2ECB1458
481B5C976GIH3DEA2F
6H2G97DAEF35B4I8C1
FE5A3DB418CI7G269H
81I4CB7GH692DA5F3E
E5CFDA48I1B9G63H72
H2367GAF5EDC4891BI
1I98B4G62H73AFCED5
5CBEAF819I476HD2G3
I971486H32GDFEB5AC
23DHG6FEC5AB817I49
97GI81H2D36AE54CFB
CB45FE1I798GH2A36D
3DA26HE5BCF41IG987
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.