Quick answers about the games, devices, accounts and future SudokuGG modules.
Yes. Classic Sudoku, Daily Sudoku, the printable generator and Kalkudoku can be used without payment. There is no paywall between you and a playable puzzle. The site may use clearly separated advertising in the future to support hosting and development.
No. You can open a puzzle without registering or signing in. Game progress and preferences may be stored locally in your browser, so clearing site data or moving to another device can remove an unfinished game or local record.
Classic Sudoku, Daily Sudoku, Printable Sudoku and Kalkudoku are playable. Mystery Sudoku is marked Coming Soon while it is being developed. A future module is not counted as a playable game until its rules and interface are complete.
Classic Sudoku lets you choose Easy, Medium, Hard or Expert and start another puzzle whenever you want. Daily Sudoku gives every visitor the same date-based challenge, saves that date's progress locally and tracks a local streak. Both use standard 9×9 Sudoku rules.
Start with Easy Sudoku while learning to scan rows, columns and boxes. Move to Medium when you can find most singles without hints. Hard and Expert are better after you are comfortable writing candidates and checking eliminations. Difficulty depends on the solving path, not only the number of starting clues.
Yes. The live modules are designed for phone, tablet and desktop screens. Touch controls are provided on mobile, while the playable boards also accept a keyboard on desktop. If an effect is reduced by your device or operating-system motion setting, the puzzle remains playable.
In Classic and Daily Sudoku, select a cell and press a number key to enter a value. Arrow keys move between cells. Notes mode lets a number become a small candidate rather than a final answer. Exact shortcuts can vary by module, so the visible number pad remains available.
A number conflicts when it does not match the puzzle's completed solution or breaks the active game's rules. In standard Sudoku, a row, column and 3×3 box cannot contain the same digit twice. Use Undo or Erase, then check all three areas before trying another value. The mistake guide explains a reliable checking routine.
Notes record possible candidates in an empty cell; they are working marks, not final answers. Hints reveal or guide a useful next move when you are stuck. Try a full scan first, because finding the next logical placement yourself is the best way to build a repeatable solving method.
Yes. Open Printable Sudoku, choose the difficulty and number of puzzles per A4 sheet, then generate the set. You can include a separate solution page. Use the browser print dialog to print on paper or save a PDF if that option is available on your device.
The generator builds each sheet from a valid solved grid and includes the matching solution. Puzzle quality is checked by the generation logic before display. If you encounter a repeated or unsatisfactory puzzle, send the difficulty and visible grid through the contact page so it can be reproduced and reviewed.
Kalkudoku combines a Latin-square rule with arithmetic cages. In an N×N board, each row and column uses the numbers 1 through N once. Cells inside a cage must reach the printed target using its operation. Read the Kalkudoku rules before your first grid.
Classic Sudoku does not. The digits act as symbols, and the solution comes from logic. Kalkudoku does use basic arithmetic because its cages have targets and operations. You can play Classic Sudoku even if you do not consider yourself good at mathematics.
Sudoku Run is not part of the current public collection. It may return after it is redesigned and tested, but the site does not promise a release date. Keeping an unfinished mode out of the main navigation makes it clearer which games work now.
Current modules can use local browser storage for an unfinished puzzle, selected theme, timer, preferences, Daily Sudoku streak and similar game data. It is not an account or cloud backup. See the Privacy Policy and Cookie Policy for details and deletion options.
Use the contact page and include the exact page, device, browser and steps that reproduce the issue. For a content correction, quote the sentence and explain what is wrong. For a puzzle problem, include the difficulty, date if it is a Daily Sudoku, and a screenshot when possible.