Suirodoku is a color-based sudoku variant that adds a fourth constraint to classic sudoku. Unlike traditional sudoku, each cell combines a number and a color, creating 81 unique pairs. Here are quick answers to the most common questions.
Quick answers to the most common questions about Suirodoku.
Sudoku with colors. Each cell has a number (1-9) AND a color (9 colors). This creates 81 unique pairs.
Same as Sudoku (rows, columns, 3×3 regions must have 1-9) + one extra rule: each color must also contain 1-9. See The 4th Combination.
Not necessarily. Colors give you more information to work with. It's different, not harder. Read Suirodoku vs Sudoku.
It helps, but isn't required. If you know Sudoku, your skills transfer directly. If not, you can learn both together with our tutorial.
Exclusive techniques that only work in Suirodoku. Rainbow tracks numbers across colors. Chromatic Circle tracks colors across numbers.
Yes. Play unlimited puzzles for free at suirodoku.com.
Follow our Training Plan: start with Easy, learn the techniques at Hard/Expert, then tackle Master puzzles.
Yes! Check the leaderboards to see global rankings by difficulty level.
Want to Learn More?
Want to Learn More?
Explore our full article collection:
- Rainbow Technique — Find colors by tracking numbers
- Chromatic Circle — Find numbers by tracking colors
- 81 Unique Pairs — Why every cell is different
- Suirodoku vs Sudoku — The key differences
- The 4th Combination — The extra rule explained