Terms of Service

These terms govern your use of StockFishy: the browser extension, the account system, and stockfishy.com. By installing the extension or creating an account, you agree to them.

The service

StockFishy is a browser extension for Chess.com and Lichess.org that rates legal chess moves using the Stockfish engine, running locally in your browser, to help you study and understand positions. It's an educational tool.

Fair play is your responsibility. Chess.com, Lichess, and most other platforms prohibit engine assistance during rated or live games and may suspend accounts that use it. StockFishy doesn't police how or when you use it, that's on you. Use it in a way that's consistent with the rules of whatever platform you're playing on.

Accounts

• You need a Google account to sign in. You're responsible for keeping access to it.
• One account per person. Don't share logins to get around daily usage limits.
• You can request account deletion at any time. See the Privacy Policy for how.

Plans, billing, and cancellation

• Free plan. A limited number of analyzed positions per day, at no cost, indefinitely.
• Paid plans (Starter, Pro, Unlimited) raise your daily limit and bill monthly in advance through Stripe. Subscriptions renew automatically each month until cancelled.
• Cancelling stops future renewals; you keep your paid plan's limit through the end of the period you already paid for, then drop to the Free plan. Cancel any time from your account page via the Manage Billing link, which opens Stripe's billing portal.
• Refunds aren't offered automatically for partial billing periods. If something's genuinely wrong, like a billing error or a duplicate charge, email us and we'll sort it out.
• We may change plan pricing or daily limits going forward. Changes won't apply retroactively to a period you've already paid for.

Acceptable use

Don't use StockFishy to abuse, scrape, or overload Chess.com, Lichess, or our own servers; don't try to circumvent daily usage limits or account restrictions; don't reverse-engineer or resell the extension.

No warranty

StockFishy is provided "as is." Move ratings come from the Stockfish engine and are for educational purposes. We don't guarantee they're error-free, and we're not responsible for game outcomes, rating changes, or platform enforcement actions (like suspensions) that result from how you use the tool.

Limitation of liability

To the extent permitted by law, StockFishy's liability for any claim relating to the service is limited to the amount you paid us in the 12 months before the claim arose.

Changes to these terms

We may update these terms as the product changes. Material changes will be reflected here with an updated date; continued use after a change means you accept the update.