How accurate is this?

Within ~1 minute for mid latitudes — fine for everyday photography, gardening, or schedule planning. Refraction is approximated to the standard −0.833° offset used by NOAA. For high-precision astronomy use a dedicated ephemeris library.

Why blank values near the poles?

In polar summer the sun never sets (no sunset row) and in polar winter it never rises (no sunrise row). Twilight rows are blank when the sun doesn't dip far enough below the horizon for that phase either.

Sunrise & Sunset Calculator

Time

Implements the simplified NOAA solar position equations: from a date and a (lat, lng) pair, it derives the solar declination and hour angles for each event. Civil twilight = sun 6° below the horizon (when artificial light starts being needed), nautical = 12° (horizon still visible at sea), astronomical = 18° (the sky is fully dark). When the sun never crosses the relevant altitude — polar day or night — the row is left blank and a note appears.

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Presets

LatitudeLongitudeDateTime zone

Astronomical dawn15:22:56
Nautical dawn16:05:17
Civil dawn16:43:15
Sunrise17:13:49
Solar noon00:31:13
Sunset07:48:38
Civil dusk08:19:12
Nautical dusk08:57:10
Astronomical dusk09:39:31
Day length14h 34m 49s

NOAA simplified algorithm. Twilight phases: civil 6°, nautical 12°, astronomical 18° below horizon.

How to use

Pick a preset or punch in your own latitude / longitude (negative = south / west).
Set the date.
Adjust the time zone — the algorithm computes in UTC and the display reformats.

Frequently asked questions

How accurate is this?: Within ~1 minute for mid latitudes — fine for everyday photography, gardening, or schedule planning. Refraction is approximated to the standard −0.833° offset used by NOAA. For high-precision astronomy use a dedicated ephemeris library.
Why blank values near the poles?: In polar summer the sun never sets (no sunset row) and in polar winter it never rises (no sunrise row). Twilight rows are blank when the sun doesn't dip far enough below the horizon for that phase either.