Contact Us
Have a suggestion for a new calculator, found a discrepancy in our solar data, or want to say hello? We'd love to hear from you. SunCalc is maintained by a small team and we read every message we receive.
How to Reach Us
Email us at: [email protected]
We aim to respond within 2 business days. For accuracy reports, please include your location (latitude/longitude or city name), the date you used, and the expected versus calculated result. Comparing against a reliable reference (NOAA, US Naval Observatory, or a dedicated astronomy app) helps us pinpoint discrepancies quickly.
What We Love to Hear About
- Accuracy reports: If our sunrise, sunset, or golden hour times differ significantly from a trusted reference for your location and date, please report it. Include your coordinates, date, timezone, and the reference you're comparing against.
- New calculator requests: Is there a solar calculation SunCalc doesn't cover? Moon phase integration, solar panel output estimator, UV index predictor, solar eclipse times? Tell us what would be most useful for your work.
- Polar location issues: Locations near the Arctic or Antarctic circles can experience midnight sun or polar night. If our tools handle these edge cases incorrectly, we want to know.
- Timezone and DST issues: Solar times are highly sensitive to timezone and daylight saving transitions. If times seem off by an hour around DST changes, please report your location and date.
- General feedback: Usability, design, and content — we read and consider all of it.
What SunCalc Covers
SunCalc offers free calculators for sunrise and sunset times, golden hour, blue hour, solar elevation and azimuth, day length, solar noon, and civil/nautical/astronomical twilight — for any location on Earth. All tools are free and require no registration.
Response Times
General inquiries and suggestions: within 2 business days. Accuracy reports with location data: within 1 business day. We do not respond to unsolicited marketing messages.