Privacy Policy

Last updated: June 9, 2026

Overview

NumStack ("we", "our") operates numstack.net. This Privacy Policy explains how we handle information.

Information We Collect

Automatically Collected

  • Google Analytics: Pageviews, user flow, device type. Aggregated and anonymized only.
  • Server logs: IP addresses, browser type, pages visited.
  • Cookies: Essential cookies only (no tracking cookies).

Information You Provide

  • Calculator inputs: NOT stored or logged. Used only for real-time calculations.
  • Email (optional): If you sign up for updates, we store your email.
  • Contact form: If you contact us, we store your message.

How We Use Your Data

We use data to:

  • Understand site usage patterns
  • Improve calculator accuracy and performance
  • Fix bugs and improve user experience
  • Send you updates (only if you opted in)

Data Sharing

We do NOT share your data with third parties, except:

  • Google Analytics: Aggregated, anonymized analytics
  • Law enforcement: If required by legal process

Security

We use HTTPS encryption on all pages. Your data is stored securely and not transmitted insecurely.

Your Rights

You have the right to:

  • Request what data we have about you
  • Request deletion of your data
  • Opt out of analytics tracking
  • Unsubscribe from emails

To exercise these rights, contact us.

Third-Party Services

Google Analytics: Google's Privacy Policy

Railway (hosting): Railway's Privacy Policy

Changes to This Policy

We may update this policy from time to time. Significant changes will be posted here.

Contact

Questions? Email: [email protected]