Printable sudoku puzzles, easy to expert

Free sudoku books to print, sorted by difficulty: easy grids that solve without guessing, medium and hard puzzles for daily solvers, an expert set, and 4 × 4 and 6 × 6 grids for kids. Every puzzle has exactly one solution, and the answers are at the back of each PDF.

Questions

What makes a sudoku easy, hard or expert?

The number of given clues and the techniques needed. Our easy and medium puzzles (38 and 32 clues) can be finished with singles alone, so you never have to guess. Hard (27 clues) and expert (24 to 26 clues) puzzles cannot: you will need candidate pairs, pointing numbers and similar techniques.

Which sudoku should a child start with?

The 4 × 4 grids with the numbers 1 to 4, from about age 5. Once those feel easy, move to the 6 × 6 book (ages 8 to 12), then to the easy 9 × 9 puzzles.