Hard Printable Sudoku
Fewer starting numbers. You will need pencil marks to find the way through.
- 6 puzzles
- US Letter & A4
- 100% free
6 puzzles
How to play Sudoku
- Fill every empty square with a number from 1 to 9.
- Each row, each column and each 3 × 3 box must have every number from 1 to 9 exactly once.
- Start where a row, column or box is nearly full. Write small pencil marks when you are not sure.
For parents & teachers
For parents and teachers
The levels are graded by how a person solves them, not just by how many numbers are given. Easy puzzles can be finished by spotting squares where only one number fits. Medium ones also need "this number can only go here in this row". Hard ones need pencil marks.
Every puzzle has exactly one solution, checked by a computer before it is published. Each sheet is a one-page PDF in US Letter and A4, with a separate answer key so it can be handed out without spoilers.
- Print at 100% scale for the clearest grid.
- Use a pencil, not a pen.
- Easy puzzles suit most kids from about age 8 who know the rules.
Easy Printable Sudoku
Medium Printable Sudoku