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Loading contentSource-backed sunrise, sunset, solar noon, day length, and civil, nautical, and astronomical twilight for any location and date — computed from public-domain solar formulae and timestamped. Enter a latitude and longitude; your location is used only for the calculation and is never stored.
Privacy: your location is used only for this calculation and is not stored. No browser geolocation or IP lookup is used — coordinates come only from what you type. Times are shown in the timezone you enter (UTC if blank).
Enter a latitude and longitude to compute sunrise, sunset, solar noon, day length, and the three twilight phases. Nothing is shown until you do — no location is assumed.
Sunrise and sunset are the moments the Sun's centre sits 0.833° below the horizon — allowing for atmospheric refraction and the Sun's radius. Solar noon is when the Sun crosses your meridian, and day length is the time it spends above that horizon. The times above are computed from public-domain solar formulae and timestamped; they assume a flat, sea-level horizon and do not model local terrain.
Between day and full darkness the sky passes through three twilight phases. Their times for your location appear in the calculator above; see the twilight page for more.
Facts on this topic will be cited from these primary and reference sources.
Public-domain solar-position geometry: sunrise, sunset, solar noon, twilight, declination, and the equation of time.
Public domain (US Government work).
Precise time, almanac data, Sun/Moon rise-set, and phases.