About the site

About Sudoku Slate

Free Sudoku games, puzzle checking, printable sheets and solving guides. No account required.

Games and tools

Play Sudoku

Choose a difficulty, keep candidate notes and continue an unfinished game saved in this browser.

Play Sudoku

Daily Sudoku

Everyone gets the same puzzle for the same UTC date. Your completion record stays on your device.

Daily Sudoku

Learn Sudoku

Learn candidates, singles and other techniques through worked examples.

View guides

Print Sudoku

Create clear printable sheets in A4 or Letter, with an optional answer key on a separate page.

Print a Sudoku

Puzzle catalog and methods

The current catalog contains 512 puzzles generated for this site. Each has a checked unique solution and a reproducible difficulty rating based on the logical techniques used to solve it. The catalog is finite, and puzzles repeat after its documented cycle.

The lessons use worked examples with specific cells, candidate sets and conclusions. The solver checks for conflicting clues, no solution, multiple solutions or a unique answer.

Puzzle generation and grading

Languages and saved progress

Core games, tools and introductory guides are available in eight languages. Additional research and technique guides are available in the languages shown in each page’s language menu.

Games, notes, display preferences and completion records are stored in your browser. There is no account-based backup or cross-device sync. Read the privacy page for the details and your choices.

Site operator

For corrections, accessibility feedback or questions, contact contact@sudokuslate.com. Including the page address and puzzle ID helps us locate the issue.