About this plugin
SudokuGrid is a free WordPress plugin that adds an interactive Sudoku game to your website using a simple shortcode.
ch, SudokuGrid provides six difficulty levels, from beginner-friendly puzzles to expert challenges.
Visitors can play directly on your website, take pencil notes, check their entries, print puzzles and resume their current game.
Features
- Six difficulty levels: Baby, Very Easy, Easy, Medium, Hard and Expert.
- Sudoku puzzles with exactly one solution.
- Pencil notes for tracking possible candidates.
- Optional live error checking.
- Automatic saving and restoration of the current game.
- Responsive interface for desktop, tablet and mobile.
- Printable Sudoku puzzles for playing on paper.
- On-demand puzzle generation using AJAX.
- Conditional loading of public CSS and JavaScript.
- Built-in puzzle model library.
- Administrative auditing tools for checking puzzle models.
- No account required for visitors.
Puzzle generation
SudokuGrid uses a library of validated puzzle models and mathematical transformations to generate different Sudoku grids.
The transformations preserve the uniqueness of the solution and the difficulty characteristics of the original models.
Each generated puzzle is based on a model selected from the corresponding difficulty level.
Game saving
SudokuGrid automatically saves the current game using the browser’s localStorage feature.
Saved information includes the puzzle, entered numbers, pencil notes and selected gameplay options.
When visitors return using the same browser and browser storage, they can resume their previous game.
Saved games are stored locally in the visitor’s browser, not in the WordPress database.
Clearing browser storage or using another browser or device may prevent restoration of the saved game.
Error checking
Players can enable or disable live error checking.
When enabled, SudokuGrid compares entered numbers with the puzzle solution and highlights incorrect entries.
Pencil notes are not checked against the solution.
Performance
SudokuGrid is designed to minimize unnecessary server activity.
Public assets are loaded only when the Sudoku shortcode is used, and puzzle generation is performed on demand through WordPress AJAX.
The plugin separates public gameplay from administrative tools to avoid loading the puzzle auditing engine unnecessarily during ordinary page visits.
Actual performance depends on the hosting environment, WordPress configuration and visitor activity.
Privacy
SudokuGrid does not require visitors to create an account.
Game progress is saved locally in the visitor’s browser using localStorage.
Puzzle generation requests are processed by the website’s WordPress installation.
SudokuGrid does not require an external Sudoku generation service.