logo
How to Videos Forum Rankings Print   Hide solution 2 Apr 2013
Easy:
4×4
5×5
6×6
Killer
Sudoku
Medium:
4×4
6×6
8×8
Killer
Sudoku
Difficult:
4×4
6×6
8×8
9×9
Extra
Difficult 9 × 9, Rating: ★★★★★★      Solved 284 times

The World's Hardest Calcudoku
can you solve it?
abcdefghi
1 
21+
9
 
2
 
7
60×
3
 
5
 
1
25+
4
 
6
 
8
Clear cell
Bold cell
Toggle pencil mode
Hide buttons
Change buttons position
Undo
2 
 
2
6-
9
 
3
11+
6
 
4
4-
7
13+
5
 
8
 
1
3 
 
1
8+
7
8
8
 
5
2
2
 
3
9
9
11+
4
 
6
4 
24+
6
 
1
13+
9
 
4
25+
8
3-
5
 
2
 
7
17+
3
5 
 
7
 
8
2
2
 
1
 
9
 
6
3
3
 
5
 
4
6 
 
3
1-
4
13+
6
 
7
 
1
1-
9
 
8
11+
2
 
5
7 
26+
5
 
3
1
1
16×
8
6
6
12+
4
7
7
 
9
25+
2
8 
 
4
1-
6
 
5
 
2
378×
7
 
8
1
 
3
 
9
9 
 
8
 
5
 
4
 
9
 
3
 
2
 
6
 
1
 
7
Undo
Start over
Change puzzle size
total
All puzzles published on this site are © Patrick Min. Send your ideas and suggestions to .

Tomorrow's puzzles will appear in  hour(s) and  minute(s).Order puzzles

Articles: the 10 Hardest Logic/Number Puzzles | The 7 Easiest Puzzles | Numerical Intelligence


Server time: Wednesday 21 January 2026, 7:00:18 Central European Time.
Page processing time: 0.051 sec.
Page load time sec. (0.08)