Learn Sudoku & Kakuro

Guides, strategies, and step-by-step techniques to help you get better — from your very first puzzle to advanced solving moves. Every guide is free and written for real players.

• Start Here: Solving Your First Sudoku with Naked Singles

  The naked single is the first technique every Sudoku solver learns: a cell where only one digit can possibly go. Here is how to spot it and where to look first.

• Kakuro Combinations: The Number Blocks That Crack the Grid

  Some Kakuro clues can be filled exactly one way. Learn the handful of "magic block" combinations that experienced solvers memorize — and how to use them to break a puzzle open.

• Hidden Singles: Finding the Only Home for a Digit

  A hidden single is a digit that can go in just one cell of a row, column, or box — even when that cell still shows several candidates. It is the technique that gets you moving again when naked singles run dry.

• Pointing Pairs: Your First Intermediate Sudoku Technique

  When a digit inside a box is confined to one row or column, it clears that digit from the rest of the line. Pointing pairs are the bridge from beginner scanning to real candidate logic.

• How Sudoku Difficulty Works: From Level 1 to 100

  Sudoku difficulty is not about how many cells are blank — it is about which solving techniques a puzzle forces you to use. Here is what actually changes as the numbers climb.

• A Beginner's Guide to Kakuro: Rules, Strategy, and Your First Solve

  Kakuro is a number crossword: fill runs of cells so each adds up to its clue, with no repeated digits. If you can add to nine and spot a forced combination, you can solve one.

• How to Solve Killer Sudoku Cages

  Killer Sudoku gives you no starting digits — only cages with target sums. Learn to read a cage as a short list of digit sets, find the forced ones, and use the 45 rule to crack the grid.

• Kakuro vs Sudoku: What's the Difference and Which Is Harder?

  Kakuro and Sudoku are close cousins: both are grid logic puzzles built on the digits 1–9 with no repeats in a unit. The difference is arithmetic — and it changes which one feels harder.

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