Privacy Policy

This policy explains what information prochess.online collects, how it is used, and — more importantly — what we don't collect. Last updated: July 2026.

Summary

prochess.online is designed to be privacy-first by architecture, not just by policy. Chess analysis runs entirely inside your browser via WebAssembly. We have no server-side game processing, no user accounts, and no database of personal information. The TL;DR is: your chess games never leave your device, and we don't track you.

What We Collect

Automatically Collected Information

Like virtually every website, our hosting infrastructure logs standard technical information for each HTTP request:

• IP address (anonymized — last octet removed)
• Timestamp of the request
• Requested URL and HTTP method
• User-Agent string (browser and OS version)
• HTTP referrer (the page that linked to us)
• Response status code and size

These server logs are used exclusively for:

• Diagnosing technical issues and errors
• Detecting and mitigating abuse or DDoS attacks
• Aggregated traffic statistics (total visitors, popular pages)

Logs are retained for a maximum of 30 days and are never shared with third parties except as required by law.

Advertising

We display non-intrusive advertisements to cover hosting costs. Our advertising partners may use cookies or similar technologies to serve relevant ads. These are standard industry practices — you can manage or disable cookies through your browser settings. We do not share any personally identifiable information with advertisers.

What We Do NOT Collect

This is the important part. We do not:

• Store or upload chess games. All PGN parsing and engine analysis happens in your browser via WebAssembly. The game data never leaves your device.
• Require accounts or logins. There is no user registration system. No email, no username, no password.
• Track individual users across sessions. We don't use fingerprinting, persistent identifiers, or cross-site tracking.
• Collect personal information. We don't ask for your name, email, location, or any other personal data — unless you choose to email us via the Contact page.
• Sell or share data. We have no user data to sell, share, or monetize beyond the basic advertising model described above.

Third-Party Services

CDN (Content Delivery Network)

We use cdnjs.cloudflare.com to serve the Three.js library (used for the optional 3D particle background) and fonts.googleapis.com to serve web fonts. When your browser fetches these resources, Cloudflare and Google receive standard HTTP request information (IP address, User-Agent). These services have their own privacy policies.

External APIs (User-Initiated Only)

When you fetch games by Chess.com or Lichess username, your browser makes a direct API call to those platforms. prochess.online never proxies or sees this data. These requests are initiated by your browser, directly to Chess.com or Lichess servers.

Cookies

prochess.online itself does not set any first-party cookies. Our advertising partners may set third-party cookies for ad measurement and frequency capping. You can control cookie behavior through your browser's privacy settings.

Data Security

Since we don't collect or store user data, the primary security consideration is the transmission of the site itself. We enforce:

• HTTPS-only — all traffic is encrypted via TLS
• HSTS — browsers are instructed to never connect via plain HTTP
• Content Security Policy — restricts which scripts and resources the browser is allowed to load
• Security headers — XSS protection, clickjacking prevention, MIME-type enforcement

Children's Privacy

prochess.online does not knowingly collect personal information from children under 13. Since we don't require accounts or collect personal data, the primary consideration is the advertising displayed on the site. If you believe a child has provided personal information through our Contact form, please email us and we will delete it promptly.

Changes to This Policy

We may update this privacy policy from time to time. Material changes will be noted on this page with an updated date. For significant changes, we'll also post a notice on the home page.

Contact

Questions about this policy? Reach us at support@prochess.online or via our Contact page.