Beginner → Expert · One ladder
Sudoku strategies, in order
Learn strategies in the order strong players actually use them. Practice each stage on the live Medium board.
Play now · medium
Tap a cell, then a number
Beginner
Intermediate
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Pencil marks
Candidate notes that make pairs and eliminations visible.
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Naked Pair
Two cells, same two candidates — strip them from the unit.
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Hidden Pair
Two digits trapped in two cells — clear everything else there.
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Pointing Pair
A box confines a digit to one line — remove it down that line.
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Box/Line Reduction
Mirror of pointing: a line forces a digit out of a box.
How to use this ladder
Don't learn strategies out of order. Each stage assumes the previous one is automatic: pairs only appear once your singles are exhausted; X-Wing only matters once pairs and pointing are clean. A board that beats you is almost always beaten by the next strategy up — never by guessing.
Next reads: the six-step solving method · 12 practical tips · how to get better at Sudoku · what difficulty levels actually change.
FAQ
- What is the best Sudoku strategy?
- There isn't one — strong players stack strategies in order of cost. Scan by digit, fill every single, add pencil marks, then hunt pairs and pointing patterns. Advanced fish patterns (X-Wing, Swordfish) are for the final third of hard boards, not the opening.
- What is the fastest strategy for beginners?
- Digit scanning. Pick the digit that appears most often in the grid and sweep each box asking 'where can this go?'. It requires no notes and solves large parts of Easy boards in minutes.
- Which strategy should I learn after Naked and Hidden Singles?
- Naked Pair. It appears constantly on Medium boards and teaches the core skill of elimination-by-group, which every later pattern builds on.
- Is guessing ever a valid Sudoku strategy?
- Not for human solving. Trial-and-error (called 'bifurcation') works but teaches nothing and breaks on hard boards. Every strategy on this page is logic-only and provable.
- How do I know which strategy a stuck position needs?
- Work the ladder bottom-up: singles → pairs → pointing → box/line → fish. Our when-stuck diagnostic lists symptoms ('almost finished but two cells swap', 'box nearly full') and the strategy each one points to.