Sudoku Technique Tutorials - Sudoku World Tournament

Why Learn Sudoku Solving Techniques?

Sudoku is a game of pure logic, not luck or guesswork. Every solvable puzzle can be completed through systematic application of logical techniques. Learning these methods transforms Sudoku from a frustrating trial-and-error exercise into an elegant, satisfying logical journey.

Each technique builds upon previous ones, creating a comprehensive solving toolkit. From the fundamental Naked Singles that form the foundation, to advanced patterns like XY-Wing that reveal hidden chains, these techniques ensure you can tackle any puzzle with confidence and precision.

The Path to Mastery: Progress through these techniques systematically. Master the fundamentals before advancing to intermediate methods, and ensure intermediate techniques are second nature before tackling advanced patterns. Each technique you learn opens new puzzle-solving possibilities and deepens your understanding of Sudoku's elegant logic.

Fundamental Techniques

These are the building blocks of all Sudoku solving. Master these first.

Naked Single Beginner

When a cell has only one possible candidate remaining after eliminating all other numbers, that candidate must be the answer.

Learn Naked Single

Hidden Single Beginner

When a number can only fit in one cell within a unit (row, column, or box), it must go there, even if the cell has other candidates.

Learn Hidden Single

Intermediate Techniques

Essential techniques for solving medium to difficult puzzles.

Locked Candidates Intermediate

When candidates in a box are confined to one row or column, powerful eliminations can be made in the intersecting units.

Learn Locked Candidates

X-Wing Intermediate

A rectangular pattern across two rows and columns that forces a candidate into specific positions, allowing strategic eliminations.

Learn X-Wing

Simple Colouring Intermediate

Using alternating colours on conjugate pairs to identify contradictions and reveal eliminations through logical chains.

Learn Simple Colouring

Advanced Techniques

Powerful patterns for tackling expert-level puzzles.

Swordfish Advanced

An extension of X-Wing using three rows and columns, creating a more complex elimination pattern for difficult puzzles.

Learn Swordfish

XY-Wing Advanced

A forcing chain using three bi-value cells that creates logical implications, guaranteeing eliminations through pure reasoning.

Learn XY-Wing

Recommended Learning Path

Start with Naked Single and Hidden Single – These form the absolute foundation. Practice until you can spot them instantly.
Master Locked Candidates – This is the critical bridge between basic and advanced techniques. It changes how you see the grid.
Learn X-Wing – Your first pattern-based technique. It introduces the concept of systematic elimination through geometric patterns.
Add Simple Colouring – Introduces logical chains and alternating possibilities, building analytical thinking.
Progress to Swordfish – Builds on X-Wing principles with increased complexity, preparing you for advanced pattern recognition.
Master XY-Wing – The gateway to forcing chains and advanced logical reasoning. Completion of XY-Wing marks your arrival at advanced-level solving.

Remember: Learning these techniques is a journey, not a race. Each technique requires practice before it becomes intuitive. Work through puzzles at the appropriate difficulty level, applying each new technique until it feels natural. The satisfaction of solving a challenging puzzle through pure logic—with no guessing—makes every moment of learning worthwhile.