Privacy Policy

Last updated: 21 July 2026. TCG AI SIM is a free, non-commercial fan project. This page is written in plain language to explain how the site works — it is not legal advice.

This Privacy Policy explains what information TCG AI SIM (“the site”, “we”, “us”) collects, why we collect it, and the choices you have. We collect only what the site needs to work. We do not sell your data, and we do not use advertising or cross-site tracking.

Who this applies to

Anyone can browse the cards, decks, and rankings without signing in. You only provide personal information if you choose to sign in to save decks and track a collection.

What we collect

  • Account information (only if you sign in): when you sign in with Google we receive your name, email address, profile picture, and Google account identifier. We use this to create and identify your account.
  • Content you create: the decks you save and the card collection (“inventory”) you record, along with deck ratings produced by the simulator.
  • Preferences: settings such as your light/dark theme and view filters, stored in your browser’s local storage on your device.
  • Diagnostics: anonymous crash and error reports, used only to find and fix bugs.
  • Bug reports: if you submit a bug report, we store the description you provide, a short title derived from it, the page where you submitted it, basic browser and viewport details, and the account that submitted it. We use this only to investigate and resolve the report.
  • Usage analytics (only if you accept): if you accept analytics in the cookie notice, we record which features you use (for example opening a card, saving a deck, or viewing a replay) through PostHog. If you are signed in, this activity is linked to your account so we can understand how the site is used and improve it. You can decline, and nothing analytics-related is collected.
  • Technical logs: standard server logs (such as IP address, request time, and browser type) generated automatically when you use the site, kept for security and debugging.

How we use it

  • To provide the site — sign-in, saving decks, and tracking your collection.
  • To keep you signed in across visits.
  • To diagnose, fix, and prevent errors and abuse.
  • To receive, investigate, and track bug reports you choose to submit.
  • With your consent, to understand which features are used and improve the service (usage analytics).
  • To operate, secure, and improve the service.

Cookies and local storage

Most of what we store is essential or functional: a login token and Google sign-in session cookie (only if you log in), your preferences in local storage, and anonymous diagnostics. These are needed for the site to work and are set regardless of your choice.

The one non-essential category is analytics: with your consent, PostHog sets a usage analytics cookie. It is off by default — nothing is captured until you accept in the cookie notice, and you can decline. There is no advertising or cross-site tracking. You can change your mind at any time by clearing this site’s storage in your browser settings, which makes the notice reappear so you can choose again.

Third-party services

We rely on a small number of providers to run the site:

  • Google — sign-in (Google Sign-In). Google’s handling of your data is governed by Google’s own privacy policy.
  • Google Cloud — hosting and infrastructure for the application and database.
  • Sentry — anonymous crash and error reporting.
  • PostHog — product/usage analytics, used only if you accept analytics. PostHog processes this data on servers in the European Union.

Data retention

We keep your account and the content you create for as long as your account exists. Technical logs and diagnostics are kept only as long as needed for security and debugging. When you ask us to delete your account, we remove your personal information and the content tied to it.

Your rights and choices

You can ask us to access, correct, or delete the personal information associated with your account, or to export the decks and collection you have saved. To make a request, email us at support@tcgsim.ai. Depending on where you live, you may have additional rights under laws such as the GDPR or CCPA.

Children

The site is not directed at children under 13 (or the minimum age required in your country), and we do not knowingly collect their personal information.

Changes to this policy

We may update this policy from time to time. When we do, we will revise the “last updated” date at the top of this page.

Contact

Questions about this policy or your data? Email us at support@tcgsim.ai.

See also our Terms of Use.