1. The service
Open Moon Calendar ("we", "the site") provides a free, educational moon-phase calendar: moon phases, illumination, moon age, moonrise/moonset, sunrise/sunset, night-sky and eclipse information. No account or payment is required. We may update, improve, or discontinue parts of the service at any time.
2. Accuracy disclaimer
Astronomical data is computed in-browser with established algorithms and is accurate for general, educational, and planning purposes (typically within a minute for rise/set times, subject to terrain, atmospheric refraction, and your device clock). Do not rely on it for safety-critical navigation, aviation, maritime operations, religious observance rulings, or medical decisions. Always cross-check with official sources where precision matters.
3. Acceptable use
- Use the site for lawful, personal, educational, or commercial-reference purposes.
- Do not attempt to disrupt the site, scrape it abusively, circumvent access controls, or misrepresent its data as your own official ephemeris.
- Do not use the site to collect personal data about others.
4. Intellectual property
The site's design, text, and code are protected by applicable intellectual-property laws. You may link to, quote (with attribution), and share screenshots of the site for personal or editorial use. Systematic reproduction or resale of the site's content or branding without permission is not allowed.
5. Third-party links & ads
The site may display reserved ad slots or links to third-party resources. We are not responsible for third-party content, policies, or practices. Any future advertising provider (e.g. Google AdSense) operates under its own terms.
6. No warranty; limitation of liability
The service is provided "as is" without warranties of any kind, express or implied. To the maximum extent permitted by law, we are not liable for any direct, indirect, incidental, or consequential damages arising from use of — or inability to use — the site or its data.
7. Privacy
Your use of the site is also governed by our Privacy Policy, which explains our zero-tracking, local-first approach.
8. Changes & contact
We may revise these terms; the "Last updated" date above will reflect changes. Questions? Reach us via the Contact page.