Cookie Policy
Last updated: April 19, 2026
This Cookie Policy explains how SudokuW uses cookies and similar technologies when you visit our website. We believe in transparency and want you to understand exactly what is stored on your device and why.
What Are Cookies?
Cookies are small text files that are placed on your device by websites you visit. They are widely used to make websites work more efficiently, provide a better user experience, and give information to the site owner. Cookies can be "persistent" (stored until they expire or are deleted) or "session" (deleted when you close your browser).
Cookies We Use
SudokuW uses a single cookie. We do not use any tracking, advertising, or analytics cookies.
| Name | Purpose | Duration | Type | HttpOnly |
|---|---|---|---|---|
sudoku_anon_id |
Stores a randomly generated anonymous identifier (UUID) so we can save your game progress, display name, and multiplayer rating across visits. This ID is not linked to your real identity. | 5 years | Essential / Functional | Yes |
This is the only cookie SudokuW sets. It is classified as an essential/functional cookie because it is strictly necessary for the service to remember your game progress. It is not used for tracking, profiling, or advertising.
Cookies We Do Not Use
To be completely transparent, SudokuW does not use any of the following:
- Analytics cookies (e.g., Google Analytics, Matomo, Plausible)
- Advertising or targeting cookies
- Social media cookies or plugins
- Third-party tracking cookies of any kind
- Performance or A/B testing cookies
- Session cookies (our single cookie is persistent, not session-based)
Local Storage & Session Storage
In addition to cookies, SudokuW uses your browser's local storage and session storage to save game data directly on your device. These are not cookies, but we include them here for full transparency:
| Data | Purpose | Storage Type |
|---|---|---|
| Sudoku game board state | Saves your current game so you can resume later | Local Storage (persistent) |
| Daily challenge progress | Saves your progress on the daily puzzle and tracks which days you've played | Local Storage (persistent) |
| Journey level progress | Saves your progress on each journey level | Local Storage (persistent) |
| Multiplayer difficulty preference | Remembers your preferred difficulty for multiplayer | Local Storage (persistent) |
| Multiplayer game progress | Preserves your board during an active multiplayer match | Session Storage (tab only) |
| Multiplayer host token | Authenticates you as the host of a multiplayer room | Session Storage (tab only) |
Local storage data persists until you clear your browser data. Session storage data is automatically cleared when you close the browser tab.
Third-Party Cookies
SudokuW does not set any third-party cookies. All fonts are self-hosted - no third-party font services are used. No other third-party services are loaded on our pages.
Managing Your Cookies & Data
You have full control over the data stored on your device:
- Browser cookies - You can view, block, or delete cookies through your browser settings. Look for "Privacy" or "Cookies" in your browser's settings menu.
- Local storage - You can clear local storage through your browser's developer tools (usually F12 > Application > Local Storage) or by clearing all site data in your browser settings.
- Block all cookies - You can configure your browser to reject all cookies from SudokuW. Note that this will prevent us from saving your game progress across visits, though you can still play individual games within a single session.
If you delete the sudoku_anon_id cookie, a new anonymous identifier will be generated on your next visit. Your previous game history, display name, and multiplayer rating will no longer be associated with your session.
Changes to This Policy
We may update this Cookie Policy from time to time. When we do, we will update the "Last updated" date at the top of this page. Since we currently use only one essential cookie, significant changes are unlikely - but we will document any additions here. Your continued use of SudokuW after changes constitutes acceptance of the updated policy.
Contact Us
If you have any questions about our use of cookies or this policy, please reach out to us through our Contact page.