Privacy Policy

Overview

At SleepCycleHub, we take your privacy seriously. This privacy policy explains how we handle your data when you use our sleep calculation tools and services.

What Data We Collect

By default, we collect no personal data. Specifically:

• We do NOT collect your name, email address, or any identifying information
• We do NOT require you to create an account or log in
• We do NOT track your sleep calculations on our servers
• We do NOT share your data with third parties

Where Your Data Lives

All your sleep calculations, preferences, and history are stored locally in your browser using IndexedDB technology. This means:

• Browser-only storage: Your data never leaves your device
• No server uploads: We never send your calculations to our servers
• Your device, your data: Only you have access to your sleep history
• Works offline: Our calculators work even without an internet connection

Data Retention

Since all data is stored locally in your browser, you are in complete control:

• Data persists until you manually clear it using the "Clear History" button
• Clearing your browser data will also remove your sleep history
• Uninstalling the web app or clearing site data removes all stored information
• We cannot recover your data if you delete it—it's truly gone

Analytics & Cookies

We use Ahrefs Web Analytics to understand how visitors use our site. Ahrefs Analytics:

• Does NOT use cookies
• Does NOT track you across websites
• Collects only anonymous, aggregated data (page views, referrers, device types)
• Is GDPR, CCPA, and PECR compliant

We also display Google AdSense advertisements. Google may use cookies and collect data for ad personalization. You can opt out of personalized advertising by visiting Google's Ads Settings .

Third-Party Services

Our website may contain links to third-party websites and services, including:

• Partner tool websites (displayed in footer)
• Educational resources about sleep science

These third-party sites have their own privacy policies. We are not responsible for their practices.

Your Data Export

You can export your sleep history at any time using the "Export" button on the History page. This downloads a JSON file containing all your calculations and preferences. The export happens entirely in your browser— no data is sent to our servers.

Children's Privacy

Our service is available to users of all ages. Since we do not collect any personal data, we do not knowingly collect information from children under 13.

Changes to This Policy

We may update this privacy policy from time to time. Any changes will be posted on this page with an updated "Last updated" date. We encourage you to review this policy periodically.

Contact Us

If you have questions about this privacy policy or our data practices, you can contact us through the website.

Your Rights

Since we do not collect or store your personal data on our servers, traditional data rights (access, deletion, portability) are automatically fulfilled:

• Right to access: All your data is visible in the History page
• Right to deletion: Use the "Clear History" button or clear your browser data
• Right to portability: Use the "Export" button to download your data
• Right to object: Simply don't use our services