Privacy Policy
Last updated: March 2026
Green City Index is committed to protecting your privacy. This policy explains what data we collect, how we use it, and your rights.
Anonymous Analytics
We collect minimal, anonymous usage data to understand how the site is used. Our analytics system is self-hosted on our own infrastructure and does not use cookies or third-party services. No IP address, no cookies, and no personally identifiable data is ever stored.
What we collect:
- Pages visited and scroll depth (how far you read)
- Device type (mobile, desktop, or bot -- not the specific device or browser)
- Country of origin (derived from Cloudflare network routing, not from your IP address)
- Language preference (from your browser settings)
- Referrer URL (how you arrived at the site)
- Campaign parameters (utm_source, utm_medium, utm_campaign from the URL, if present)
- User actions (map interactions, downloads)
What we do NOT collect:
- IP addresses -- never stored
- Cookies -- we do not set any cookies
- User agent strings -- only the device class (mobile/desktop) is recorded
- Personal information of any kind
We generate a short-lived anonymous visitor identifier using a SHA-256 hash of your IP address, the current date, and a monthly rotating salt, truncated to 10 characters. This identifier rotates every 24 hours and cannot be used to track you across days. Your IP address is used only for this computation and is never stored.
The legal basis for this processing is legitimate interest (Art. 6.1.f GDPR) in understanding how the site is used to improve it. Because the data is fully anonymous (it cannot be linked to an identifiable person), it falls outside the scope of personal data under GDPR Recital 26.
Analytics data is retained indefinitely. Because it is anonymous and cannot be linked to any individual, no retention limit applies under GDPR Recital 26.
Accounts and Subscriptions
When you create an account or subscribe to Green City Index Pro, we collect:
- Your email address (used for authentication and subscription management)
- Subscription status (active, expired)
- Marketing preference (opt-in only)
We use passwordless authentication via magic links. When you request to sign in, we send a one-time link to your email address. No passwords are stored.
Payments are processed by Stripe. We do not store or have access to your credit card details. Stripe handles all payment information in accordance with PCI-DSS standards.
Infrastructure
This site is hosted on Cloudflare Pages. Cloudflare may process connection data (IP addresses, headers) as part of delivering the website to you. This processing is governed by Cloudflare's privacy policy. We do not have access to this connection-level data.
Your Rights
Under GDPR and applicable data protection laws, you have the right to:
- Access the data we hold about you
- Request deletion of your account and associated data
- Withdraw marketing consent at any time
- Lodge a complaint with your local data protection authority
To exercise any of these rights, contact us at info@green-city-index.org.
Changes to This Policy
We may update this privacy policy from time to time. The "last updated" date at the top of this page indicates when the policy was last revised.
