Sudoku guides and strategies
Every Sudokumania puzzle has exactly one solution and is solved by reasoning: you never need to guess. What you do need is to know the right moves and when to use them. These guides teach them to you one at a time, in the order you'll need them.
The path follows our levels. An easy sudoku is solved with singles: scanning, and the last possible number in a cell. A medium one also asks for intersections between boxes, rows and columns. A hard one asks for pairs, triples and patterns like the X-Wing. These aren't labels picked by eye: our solver tries every puzzle and rates it by the techniques that are actually needed to finish it.
Each guide explains one technique on a real grid, taken from our puzzles, and ends with Practice: a puzzle picked on purpose, where that technique is needed to get all the way to the end.
Getting started
- Sudoku for beginners: a method for never getting stuck How to solve a sudoku without guessing: where to start, in what order to look at the grid and what to do when you get stuck. Easy
- Pencil marks in sudoku: when you need them and how to use them well Pencil marks (candidates) unlock medium and hard sudoku. When to start writing them, two ways to use them and how to read the moves inside them. Medium
Techniques
- Scanning (cross-hatching): the first sudoku technique Scanning, or cross-hatching, is the technique that solves almost every easy sudoku. How it works, a real example and how to do it quickly. Easy
- Naked single and hidden single: the two moves behind every sudoku A number is forced in two ways: the cell admits no other, or the number has no other place in its row, column or box. Here's how to spot them. Easy
- Pointing pairs and triples: the first technique of medium sudoku If a number in a box can only go in one row or column, you remove it from the rest of that line. How to spot it, with two real examples. Medium