Color Sudoku Guides & Techniques
Welcome to the complete color sudoku guide collection. Suirodoku adds a 4th rule to classic sudoku: each color must contain numbers 1-9. This creates 81 unique pairs (9 numbers × 9 colors) and unlocks exclusive solving techniques like Rainbow and Chromatic Circle. Whether you're a beginner or an expert, these guides will help you master the game.
Why Color Sudoku Feels Deeper Than Classic Sudoku
Discover how Suirodoku revolutionizes traditional Sudoku with a fourth constraint system using colors, creating 81 unique number-color pairs for enhanced puzzle solving.
Why Try Color Sudoku? 4 Concrete Reasons
Explore four compelling advantages: unique completion experience, enhanced cognitive training, strategic mastery, and innovative gaming standards.
81 Unique Pairs: The Core Rule of Color Sudoku
Explore the mathematical foundation: 81 unique number-color pairs that create absolute uniqueness, advanced solving strategies, and enhanced cognitive benefits.
The 4th Rule of Color Sudoku: What Changes Everything
Learn how Suirodoku's fourth color constraint creates quadruple interdependency, transforms search patterns, and introduces advanced solving techniques.
Rainbow Technique: Find Missing Colors in Color Sudoku
Master the Rainbow Technique: a step-by-step guide to using number patterns for color placement, advanced pattern recognition, and solving complex puzzles.
Chromatic Circle Technique for Color Sudoku
Master the Color Wheel Technique: systematic color mapping, contradiction elimination, and compatibility pattern recognition for advanced puzzle solving.
Color Sudoku Training Plan: From Beginner to Master
Comprehensive training plan: systematic skill progression from basic constraint recognition to expert mastery through foundation, intermediate, and advanced phases.
Color Sudoku vs Sudoku: What's the Difference?
Understand Suirodoku's unique position in the sudoku ecosystem: how it relates to classic sudoku, variants like jigsaw and samurai sudoku, and digital platforms.
Suirodoku FAQ: Your Questions About Color Sudoku Answered
Comprehensive solver guide and FAQ: digital tools, manual solving approaches, advanced strategies, verification methods, and common questions answered.
Color Sudoku: Rules, Types & How They Actually Differ
Color sudoku means two different things: Irodoku replaces digits with colors, while Suirodoku uses color as a 4th constraint alongside digits. Here's what separates them.
Solving Suirodoku with Google CP-SAT Solver
How to model Suirodoku as a constraint satisfaction problem with Google OR-Tools CP-SAT: 243 variables, 136 constraints, one elegant encoding trick.
3.6 Billion Grids: How Many Suirodoku Actually Exist?
We thought there were 9 Suirodoku grids. There are 3.62 billion — for a single base alone. And 99.92% of candidates don't survive the block constraint.
13 Clues Are Enough: Suirodoku Beats Sudoku's 17
Classic Sudoku needs at least 17 clues — a result that took 800 CPU-years to prove. Suirodoku only needs 13: each clue carries a digit and a color, doubling its information.
Game Rules & Scoring System
Complete guide to Suirodoku rules and scoring: 4 constraints, game modes, speed multipliers, bonus system, and competitive ranking mechanics.