Contact & Feedback

Is the moon-phase maths up to your expectation? Tick Yes / No below — it takes less than a minute. Your answers stay in your browser until you choose to email them to us.

How would you rate Open Moon Calendar overall?

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Quick tick — what meets your expectation? (0/8 answered)

Just tick Yes / No per row. Tap again to un-tick. No login, no account, works offline.

Is the moon-phase maths (accuracy) up to your expectation?

Is the illumination % and moon age info clear and correct?

Are the moonrise & moonset times accurate for your location?

Is the site fast and easy to use with no login needed?

Do you like the day / night theme and mobile experience?

Is the offline mode useful to you?

Is the translation into your language good enough?

Would you recommend this free moon calendar to others?

Feedback is aboutAnything else? (optional)

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Write to us directly — we usually reply within 2–3 days.

What helps us reply faster

Data corrections: your city or coordinates, the date, and what looked off (e.g. moonrise time).
Bug reports: your device, browser, and steps to reproduce.
Feature requests: what you'd like and how you'd use it.
Privacy questions: see our Privacy Policy first — the short version is we don't track you.