Legal notice and privacy
Last updated: 17 September 2026
Site owner
Sudoku Detective is a site by Estudio Coartada.
Contact: contacto@sudokudetective.com.
Data collected
The site uses its own counter. There are no third-party analytics services and no external scripts.
IP addresses are not stored. To tell unique visitors apart, sixteen characters of a SHA-256 digest are kept, computed from an internal key, the IP address, the browser and the date. The result cannot be reversed and is deleted after 120 days.
The following is recorded in aggregate form and without any personal identifier: pages viewed, referrer grouped by site (for example «google» or «direct»), cases opened, solved and abandoned, hints requested and case ratings.
Legal basis: legitimate interest in aggregate measurement of the site (Art. 6(1)(f) GDPR). The data is not shared with third parties and is not used for advertising or profiling.
Processor: Cloudflare, Inc., which provides hosting and the database.
Browser storage
Games in progress, the chosen language, the light or dark theme and a few usage markers are kept in the browser's local storage.
They can be removed from the browser settings.
Contact email
Messages sent to contacto@sudokudetective.com are kept for the sole purpose of answering them.
They are not added to mailing lists and are not shared with third parties. Legal basis: consent of the sender (Art. 6(1)(a) GDPR).
Bugs and suggestions form
The message, the date and time, the language, the page or case it is sent from and the type of device (mobile, tablet or computer) are stored. No name or other data is requested.
The email address is optional and is used only to reply. It is deleted together with the message.
Legal basis: consent of the sender (Art. 6(1)(a) GDPR).
External links
The site links to Amazon (book sales), Etsy (printable packs), Buy Me a Coffee (donations) and YouTube (videos). Following those links means leaving this site, and each destination's own privacy policy applies.
Links to Amazon carry no affiliate identifier and earn no commission.
Your rights
You may exercise your rights of access, rectification, erasure, objection, restriction and portability by writing to contacto@sudokudetective.com.
You may also lodge a complaint with the Spanish Data Protection Agency (aepd.es), the supervisory authority for this site, or with the authority in your own country.
Intellectual property
The cases, texts, illustrations and code belong to Estudio Coartada. Use in the classroom or in non-profit activities is permitted provided the source is credited. For any other use, please write to the contact address.
Changes
Any changes to this notice are published on this page, with the updated date.