Make free printable sudoku puzzles in seconds. Choose a 4×4 sudoku for kids, a 6×6 sudoku or the classic 9×9 sudoku, pick easy, medium or hard, and print one big puzzle or up to six per page, each with an answer key. For young children who are not ready for numbers yet, picture sudoku uses colorful shapes instead. Every puzzle is brand new, and each one is checked by a solver to make sure it has exactly one solution.
Play sudoku online
Tap a box, then tap a number (or use your keyboard). Numbers that clash with another number in the same row, column or box turn red, and matching numbers light up in yellow to help you spot patterns. Stuck? Press Hint. The clock keeps time, so you can try to beat your record.
Ready-to-print printable sudoku (PDF)
Every set below is a finished PDF with the answer keys at the end. Use Customize to load the same settings and make a fresh batch of puzzles.
How to play printable sudoku
- Know the goal. Fill every empty box so that each row, each column and each outlined box contains every number exactly once: 1 to 4 on a 4×4 grid, 1 to 6 on a 6×6 grid and 1 to 9 on a 9×9 grid.
- Start where it is crowded. Look for a row, column or box that is almost full. If only one number is missing, it must go in the last empty box.
- Scan for one number at a time. Pick a number, say 3, and look at where the 3s already are. Each 3 rules out its row and column, which often leaves just one possible box.
- Use pencil marks. On harder puzzles, write the possible numbers small in the corner of a box and erase them as you go.
- Never guess. Every printable sudoku here has exactly one solution that can be found by logic alone.
Sudoku for kids: which size is right?
| Puzzle | Good for | Clues given |
|---|---|---|
| Picture sudoku 4×4 | Ages 4 to 6: shapes and colors instead of numbers | 8 of 16 boxes (easy) |
| 4×4 sudoku | Ages 5 to 7: numbers 1 to 4 | 5 to 8 of 16 |
| 6×6 sudoku | Ages 7 to 10: a step up with boxes of 2 by 3 | 12 to 18 of 36 |
| 9×9 sudoku, easy | Older kids and beginners of any age | 40 of 81 |
| 9×9 sudoku, hard | Teens and adults who want a real challenge | 27 of 81 |
Sudoku strategies when the easy moves run out
Easy printable sudoku can be finished with scanning alone. Medium and hard puzzles need a few more tools:
- Naked single: a box where only one number is still possible once you check its row, column and box.
- Hidden single: a number that can only go in one place inside a row, column or box, even if that box has other options.
- Naked pair: two boxes in the same row, column or box that can each only hold the same two numbers. Those two numbers can then be crossed off everywhere else in that group.
- Pointing pair: when a number in a 3 by 3 box can only sit in one row or column, it cannot go anywhere else in that row or column outside the box.
With these four ideas you can solve every hard printable sudoku on this page without guessing. Sudoku as we know it was first published in 1979 in a puzzle magazine in the United States under the name Number Place, and it became a worldwide craze in the 2000s; the sudoku article on Wikipedia has the full story. Mathematicians have also proved that a 9×9 sudoku needs at least 17 clues to have a single answer, a result explained in the mathematics of sudoku.
Why printable sudoku is good for kids
- Logical thinking: each move needs a reason, which builds step-by-step reasoning.
- Concentration and patience: finishing a puzzle rewards careful, focused work.
- Pattern spotting: children learn to scan rows, columns and boxes quickly.
- No math needed: sudoku uses numbers as symbols, so it is about logic rather than arithmetic. That is why picture sudoku works just as well.
- Printable sudoku is a great calm activity for early finishers, quiet time, travel and rainy days.
Practice it as a game
Free online games for the same skill: balloon pop, memory match, races and more. No sign-up.
Frequently asked questions
7 quick answers
Is this printable sudoku free?
Yes. Print as many puzzles and answer keys as you need for home or a whole class, without an account, and tap New puzzles any time for another batch.
Does every puzzle have only one answer?
Yes. After a puzzle is made, a solver counts its solutions and only puzzles with exactly one solution are kept, so they can always be solved by logic.
What is a 4×4 sudoku?
A 4×4 sudoku is a small grid of 16 boxes split into four 2 by 2 boxes. Each row, column and box holds the numbers 1 to 4. It is the perfect first sudoku for children.
What is picture sudoku?
Picture sudoku is a printable sudoku that replaces numbers with colorful shapes such as a circle, square, triangle and star. Children draw the missing shapes so every row, column and box has one of each.
How are easy, medium and hard different?
Harder puzzles give fewer starting clues, so more boxes must be worked out. An easy 9×9 puzzle shows 40 numbers, a medium one 32 and a hard one 27.
What is the minimum number of clues in a sudoku?
A standard 9×9 sudoku needs at least 17 clues to have a single solution. Our hard puzzles use 27, which keeps them challenging but fair.
Can I print several printable sudoku puzzles on one page?
Yes. Choose 1, 2, 4 or 6 puzzles per page (9×9 puzzles fit up to 4 per page) and up to 5 pages at once. The answer keys print at the end.
More puzzles and brain teasers
- How to Solve Sudoku: Rules and Strategies for Kids and Beginners: the full guide behind this page
- Word search generator with your own words.
- Hidden message word search.
- Plot-the-points pictures on a coordinate plane.
- Color-the-number pictures on a hundreds chart.
- Spelling word scrambles for any word list.