Privacy Policy

1. Playing without an account

You can play SPUK as a guest without creating an account. In that case, your in-progress puzzle is stored only in your browser (see the Cookie Policy for details) — it's never sent to or stored on our servers, and guest games aren't saved to the leaderboard.

2. Information we collect if you create an account

• Email address — used to sign you in via a passwordless magic link, and to send that link. We don't use it for marketing.
• Profile information (name, city, country) — optional, provided by you. Used to personalize your experience and shown publicly on the leaderboard if provided. If you don't complete your profile, your games won't appear on the leaderboard.
• Game history — difficulty, time taken, hints used, and completion date for each game you finish while signed in, used to calculate your leaderboard score and ranking.
• Settings — your preferences (default difficulty, pencil mode, hint count, number pad layout, etc.), so they carry across devices.
• Feedback — if you use the Feedback page, we store your message, star rating (if given), and — for signed-in users — the email tied to your account. If you're not signed in, there's no separate email field, so we only have an email if you choose to type one into your message.

3. Location data

We do not estimate your location. City and country are entirely self-reported — you type them in yourself on the Profile page. We don't use your IP address (or anything else) to guess or fill these in on your behalf. If you haven't filled them in, your completed games are still recorded against your account, but won't appear on the leaderboard — see "Playing without an account" and "Your rights" below for what that means in practice.

4. Why we process this data

Under UK GDPR, we rely on the following legal bases:

• Contract — processing your account, settings, and game data is necessary to provide the service you've signed up for.
• Consent — for optional information you choose to provide, such as your profile details or an email in your feedback.
• Legitimate interests — for things like keeping the site secure and working properly, which we've weighed against your right to privacy.

5. Who we share data with

We don't sell your data or share it for advertising. We use the following third-party services to run SPUK, each of which processes data on our behalf:

• Supabase — our database and authentication provider. Stores your account, profile, game, and feedback data, and handles magic-link sign-in.
• Vercel — our hosting provider. Serves the site and processes requests to it (standard web server logs).
• flagcdn.com — serves the small flag images shown on the leaderboard, based on the country you enter on your profile.
• Google Analytics — only with your consent (see below). Processes anonymized-ish usage data (pages visited, general location, device type) to help us understand how the site is used. Google may process this data outside the UK.

These providers may process or store data outside the UK (e.g. in the EU or US). Where that happens, we rely on their own compliance with UK/EU data protection law, including standard contractual clauses where applicable.

We may also disclose data if required by law, or to protect the rights, safety, or property of SPUK or our users.

6. How long we keep your data

We keep your account, profile, and game data for as long as your account is active. Feedback may be retained for longer, to help us track recurring issues and improvements over time, even after an account is deleted.

7. Your rights

Under UK GDPR, you have the right to:

• Access the personal data we hold about you
• Correct inaccurate data (you can edit your profile directly on the Profile page)
• Delete your account and personal data — you can do this yourself at any time from the Settings page ("Danger Zone"). This permanently removes your account, profile, and settings, and deletes every game you've played — including removing your entries from the leaderboard entirely.
• Restrict or object to certain processing
• Request a copy of your data in a portable format

For anything beyond self-service account deletion — access requests, data portability, or objecting to processing — email us at jim@sudokuplayer.co.uk and we'll action your request. You also have the right to lodge a complaint with the UK's Information Commissioner's Office (ICO) at ico.org.uk.

8. Cookies, local storage, and analytics

SPUK uses a small number of strictly-necessary cookies for sign-in, and browser local storage to save your in-progress puzzle. With your consent, we also use Google Analytics to understand how the site is used — you're asked to Accept or Reject this the first time you visit, and can change your mind at any time. We don't use advertising or tracking cookies. See our Cookie Policy for the full details, including exactly which cookies are set and how to change your analytics consent.

9. Children's privacy

SPUK isn't directed at children under 13, and we don't knowingly collect data from children under that age. If you believe a child has provided us with personal data, please email jim@sudokuplayer.co.uk and we'll remove it.

10. Changes to this policy

We may update this policy from time to time. We'll update the "Last updated" date above when we do — for significant changes, we'll aim to make that clear on the site.

11. Contact

Questions about this policy, or want to exercise your rights? Email jim@sudokuplayer.co.uk, or get in touch via our Feedback page.