Estimate sunrise, sunset and twilight for a manual location and local date, with explicit IANA time zone and polar-day/night handling.
Your input
Outputs are cleared when the input changes.
Result
Enter your data or use the example, then run the tool.
Worked example
For Taipei on 2026-11-09, the table shows a full local date/time plus each absolute UTC instant. At latitude 90° on 2026-06-21, absent sunrise/set events are shown as no occurrence and the day is marked polar day.
Method
Resolve local calendar noon by round-tripping Intl time-zone offsets, then call the pinned SunCalc.getTimes with latitude, longitude, height and that day’s explicit UTC offset. Format returned absolute instants in the selected IANA zone and retain null events plus alwaysUp/alwaysDown flags.
Limits
Dates 2000–2100; height 0–10000 meters. Results are astronomical estimates, not weather/visibility predictions or navigation/safety advice. Buildings, terrain and refraction affect observations. Time-zone data depends on the browser; the upstream calendar-day argument uses the noon offset, so unusual offset changes and rare duplicate events have model limitations. No location or weather API is used.
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