Your data
Privacy and local storage
Browser storage, hosting requests and your analytics choices.
No account required
Sudoku Slate does not require a name, email address or account to play. Entered clues, notes and saved games are not uploaded to a game database. Your browser performs gameplay and puzzle-checking calculations.
This website is operated from Singapore.
Page requests go to the hosting provider and are not anonymous to that infrastructure. A puzzle in the page URL is included in the request.
Browser storage
| Data | Purpose and retention |
|---|---|
| Saved puzzles | Puzzle identity, your entries and notes, selected cell, elapsed time, mistakes, hints used, pause and completion state, and up to 80 undo steps. These let you resume in the same browser. There is no automatic expiry for saved games. |
| Completion history | Up to 730 first-completion records, containing puzzle ID, difficulty, daily date when applicable, completion time, elapsed time, mistakes and hints. Newer records replace older ones after this limit. |
| Recovery copies | If two tabs try to save the same puzzle, a separate copy keeps the conflicting entries and the time that copy was saved. Repeated conflicts in the same tab update its copy for that puzzle. These copies do not expire automatically; use Delete recovery copies below that puzzle to remove them without deleting the main saved game. |
| Preferences and current puzzle | Theme choice, puzzle sequence and the active puzzle for each game mode. An earlier saved-game entry may remain locally after migration so the original record is preserved. |
| Privacy choice | Your optional analytics choice is stored locally so the site can respect it on later visits. You can change the choice below. |
These records use browser site storage. They remain on this device until you or your browser remove them, except for the completion-history limit above. Private browsing, blocked storage, low disk space or browser cleanup may prevent saving or remove existing data. There is no server backup or cross-device sync.
Saving also needs browser support for coordinating writes across open tabs. If another tab has saved a newer version, the game pauses automatic saving and lets you choose which progress to use. If it cannot save safely, it tells you and you can keep playing without a saved copy. Time is saved periodically; abruptly closing or terminating a page can lose the most recent few seconds of elapsed time.
The solver keeps typed or pasted clues in the open page’s memory and passes them to a local Web Worker. It does not send those clues to a remote solving service or save the standalone solver input as a game archive. Clipboard access is used only when you select a copy control.
Hosting and request data
The website is hosted on Cloudflare. Delivering and protecting the site involves processing technical request information, such as the requested address, network address and request timing. Hosting and diagnostic logs may retain request metadata to operate the site and investigate failures or abuse.
Cloudflare describes its handling of service and end-user information in its privacy policy. Declining optional analytics does not prevent the requests needed to load and operate the website.
Optional analytics
When configured and regional default collection is enabled, Google Analytics starts automatically outside the European Union. In EU countries, or when the country is unknown, it starts only after you allow it. Your saved refusal and Global Privacy Control keep analytics off.
When enabled, Google Analytics measures page views and game actions. Events may include a public puzzle ID, a random per-game reference, language, difficulty, result, duration and counts. Puzzle contents and notes are not sent.
Cloudflare uses the request's country to select an analytics policy. We do not request your precise location. This check returns no IP address or location details and the policy is not saved to browser storage.
Only choices you make are saved. Regional default activation is never saved as consent. You can turn analytics off using Privacy choices.
Our retention policy for user-level and event-level analytics data is two months. Aggregated reports may be retained longer. Google may process analytics data outside Singapore.
Google may process device and browser information and use cookies when its service is active. See how Google uses information from partner sites. Changing your choice stops future optional collection by this site; it does not erase information already sent to a provider.
Advertising and external links
This site does not currently display AdSense ads.
External websites have their own privacy practices and are outside our control. If you send an email, your email provider and the recipient process the message and its contents.
Delete data or change a choice
- To remove only the local completion list, use Clear completion history on the daily page. This does not remove saved games.
- To remove saved games, notes, preferences and local completion records, open your browser’s privacy or site-data settings, find this website and delete its stored data. Close open game tabs first so they do not save the current game again.
- Use Analytics preferences above to allow or turn off analytics. Clearing site data removes your saved choice; on the next visit, the current regional policy applies unless Global Privacy Control keeps analytics off.
Cleared local progress cannot be restored by the website. Removing local site data does not delete hosting logs or information previously received by an external provider.
For privacy questions about this website, contact contact@sudokuslate.com. Include only the information needed to describe your question.