Ceedoku is a free, lightweight Sudoku game designed to provide a simple and powerful Sudoku experience without unnecessary distractions.
Ceedoku runs directly in your web browser and can also be installed as an app for offline use.
Ceedoku is a Sudoku game built with the goal of keeping Sudoku simple.
There are no advertisements interrupting gameplay, and the game provides a range of features while remaining lightweight enough to run on a wide range of devices.
Whether you want to play a quick Sudoku puzzle or work through one of the harder difficulty levels, Ceedoku is designed to stay out of the way and let you play.
Ceedoku includes eight difficulty levels:
- Easy
- Medium
- Hard
- Expert
- Master
- Extreme
- Impossible
- Godlike
Each difficulty provides a different challenge, with Godlike being the most restrictive difficulty.
Ceedoku includes several tools to help with solving puzzles:
- Pencil mode
- Erase mode
- Undo
- Redo
- Hints
These tools can be enabled or disabled through the settings.
Ceedoku can save your current game so you can leave and return to it later.
The save system stores things such as:
- The puzzle
- The solution
- Entered numbers
- Pencil notes
- Selected cell
- Difficulty
- Timer
- Mistakes
- Undo and redo history
- Game state
Ceedoku also has its own save-file format, Ceedoku Save Format (.csf), which can be used to export and import saves.
Ceedoku supports both:
- Dark mode
- Light mode
The interface is designed to adapt to different screen sizes, including desktop and mobile devices.
Ceedoku also includes:
- Keyboard controls
- Arrow-key cell navigation
- Arrow-key wraparound
- Animations
- Sound effects
- Haptics
- Hint cooldowns
- Offline support
- Responsive layouts
Ceedoku does not include advertisements.
The goal is to keep the game focused on Sudoku instead of filling the interface with advertisements or other distractions.
You can play Ceedoku directly in your browser:
No installation is required to play the web version.
Ceedoku can be installed in several ways.
Supported browsers can install the website as an application, allowing Ceedoku to appear like a normal app on your device.
Ceedoku also has a desktop version packaged as an executable application.
See the installation and download pages on the Ceedoku website for more information.
Once installed, Ceedoku can be used without an internet connection.
The application keeps the required files locally so that the game can continue working when the device is offline.
Ceedoku uses its own save format:
.csf
Ceedoku Save Format is designed specifically for Ceedoku save data.
The format includes validation data so that invalid or damaged save files can be detected.
More information about the format can be found in the CSF specification:
https://ceedoku.github.io/csfspec/
Ceedoku is primarily a web application.
The game interface is built using standard web technologies:
- HTML
- CSS
- JavaScript
Puzzle generation is handled by JavaScript, with puzzle generation capable of being moved into a Web Worker so that generating difficult puzzles does not unnecessarily block the interface.
The game also uses browser storage for things such as saved games and best times.
The repository contains the source code used to build and run Ceedoku.
Some of the important parts of the project include:
- The main game interface
- Sudoku generation and solving logic
- Save and load functionality
- Settings
- Keyboard controls
- Animations
- Audio and haptic features
- Service-worker/offline functionality
- CSF save-file support
Ceedoku is developed primarily using HTML, CSS, and JavaScript.
To work on Ceedoku, clone the repository and open the project in your preferred development environment.
Because Ceedoku is a web application, most development can be tested directly in a modern web browser.
The official Ceedoku website homepage is:
https://ceedoku.github.io/home
The website contains information about the game, installation instructions, downloads, the changelog, and other project information.
Note:
https://ceedoku.github.iois the direct link to the Ceedoku game. It does not open the website homepage.
Changes between Ceedoku versions are documented in the changelog:
https://ceedoku.github.io/changelog
The current version is displayed on the Ceedoku website and in the project's release information.
For the latest release, see the GitHub releases page:
https://github.com/ceebug/ceedoku/releases
Ceedoku is actively developed and may continue to receive new features, improvements, and bug fixes.
The project is still evolving, so some parts of the application may change between releases.
Ceedoku — Sudoku, without the nonsense.