Legal

Welcome to ClutchChess. By creating an account or using this site you agree to these terms. If you do not agree, please do not use the service.

1. The service

ClutchChess is a free chess training website that grades how you decide under time pressure. ClutchChess runs the service. We may add, remove, or change features at any time, including future paid features.

2. Eligibility

You must be at least 13 years old to use ClutchChess, or older if your country requires a higher minimum age for online accounts.

3. Your account

You are responsible for keeping your password safe and for activity on your account. Pick a username that is not impersonating someone else, offensive, or used to spam. We may suspend or remove accounts that violate these terms.

4. Acceptable use

Don't do anything that would degrade the service for other users. That includes: scraping puzzles or ratings in bulk, attempting to bypass the rating system, automating play with external engines to inflate your rating, sending malicious traffic, or attempting to access accounts that are not yours. We may rate limit, suspend, or terminate accounts that engage in any of the above.

5. User content

You can submit reports about specific puzzles and link your Chess.com or Lichess usernames. By submitting this content you grant us a non-exclusive license to use it for operating and improving the service. Keep notes and reports civil; abusive or harassing content will be removed.

6. Intellectual property

The ClutchChess name, logo, copy, code, and rating system are owned by the operator. Puzzles are sourced from third parties under the licenses noted in the Acknowledgments section; the puzzles themselves are not ours and remain governed by their original licenses.

7. No warranties

The service is provided as is, without warranties of any kind. Ratings, recommendations, and analyses are for training purposes only. We do not guarantee uptime, accuracy of any particular evaluation, or that the service will be free of errors.

8. Limitation of liability

To the maximum extent permitted by law, the operator is not liable for any indirect, incidental, special, or consequential damages arising from your use of the service. The total liability for any direct damages will not exceed the amount you have paid to use the service in the past 12 months, which for free accounts is zero.

9. Termination

You can delete your account at any time from the settings page. We can terminate or suspend access at any time for violation of these terms or for legal reasons. On deletion, your account data is removed as described in the Privacy Policy.

10. Changes to these terms

We may update these terms when the service or applicable law changes. The “last updated” date at the top reflects the most recent revision. Continued use after a change means you accept the updated terms.

11. Governing law

These terms are governed by the laws of the jurisdiction where the operator resides. Disputes will be resolved in the courts of that jurisdiction unless required otherwise by mandatory law in your country of residence.

12. Contact

Questions about these terms? Email nmgrind44@gmail.com.

This policy describes what data ClutchChess collects, why, and what you can do about it.

What we collect

• Account information. Your email address, a hashed password (we never see your plain password), the username you pick, and a creation timestamp. If you sign in with a third-party provider, we also receive the identifier they provide.
• Training data. Your rating, sub-ratings, drill attempts, the moves you played, time spent per move, and outcomes. This is what makes rating and recommendations work.
• Optional linked accounts. If you link Chess.com or Lichess, we store the username you provided and a cached summary of your recent rated games to surface weakness patterns.
• Technical data. Standard server logs may include IP address, user agent, and request paths for security and abuse prevention. These are kept short term.

What we don't collect

We do not run third-party advertising trackers. We do not sell your data. The puzzle engine (Stockfish) runs in your browser via WebAssembly, so the positions you analyze are not sent to our servers.

How we use it

• To run the rating system, leaderboard, and your training history.
• To generate personalized drill recommendations when you link an external chess account.
• To send account email (signup confirmation, password reset).
• To detect abuse and keep the service stable.

Service providers

We rely on a few infrastructure providers to run the service. They process some of your data on our behalf:

• Supabase for authentication and the Postgres database that stores account and training data.
• Vercel for web hosting and request routing.
• Upstash Redis for rate limiting (IP-keyed, short retention).
• Anthropic for generating the Coach's Notes that appear after solved puzzles. Notes are produced once and cached; your specific moves are not sent.
• Chess.com and Lichess public APIs, used only when you link an account, to fetch your own recent games.

Cookies

We use a session cookie (HTTP-only) so you stay signed in. Sound and board appearance preferences are stored in your browser's local storage; they never leave your device.

Your choices

• Update your account (username, password, linked chess accounts) on the settings page.
• Delete your account on the same page. Deletion removes your profile, ratings, drill attempts, and linked usernames. Anonymized aggregate counts (such as “total solved today”) may persist.
• Email questions or requests to nmgrind44@gmail.com. If you are in a jurisdiction with statutory data rights (EU/UK GDPR, California CPRA, etc.), we will honor lawful access or deletion requests.

Where data is stored

Servers and databases are hosted in the United States. If you are using the service from outside the US, your data will be transferred there for processing.

Children

ClutchChess is not directed at children under 13. If you believe a child has created an account, contact us and we will remove it.

Changes

Material changes to this policy will be reflected in the “last updated” date above. If a change meaningfully expands what we collect or how we use it, we will notify signed-in users by email.

ClutchChess builds on several open projects and freely available datasets. We're grateful for the work behind each one.

Lichess puzzle database

The puzzle library is sourced from the Lichess open puzzle database, released under Creative Commons CC0 1.0. ClutchChess is an independent project and is not affiliated with or endorsed by Lichess.

Stockfish

Position evaluation and engine play use Stockfish, a strong open-source chess engine, licensed under the GNU General Public License v3. The engine runs in your browser via WebAssembly.

Other open-source libraries

The site is built on Next.js, React, TypeScript, Tailwind CSS, chess.js, and react-chessboard, among others. The full dependency list is in the project's package manifest and each library is used under its own license.

Trademarks

Lichess, Chess.com, and other product names mentioned on this site are the property of their respective owners and are used here for identification only.