Daylight Hours Calculator

Because the sun's declination -- effectively which hemisphere is tilted toward the sun -- swings through the year as Earth orbits, cycling between roughly +23.4° and -23.4°. A northern latitude gets long days when declination is positive (northern summer) and short days when declination is negative (northern winter), so the same location's daylight hours can differ by several hours, or even go from midnight sun to polar night, purely from the date changing.

Both occur when a location's latitude, combined with the sun's declination that day, pushes the sun's hour angle beyond a full day-night cycle -- the sun simply never dips below the horizon (midnight sun) or never rises above it (polar night). This calculator flags both cases explicitly rather than reporting a sunrise/sunset time that wouldn't exist, and they occur inside the Arctic and Antarctic Circles during their respective summer and winter seasons.

Several things separate this calculator's numbers from your phone's. It reports solar time corrected by the equation of time -- a small, date-dependent adjustment (typically a few minutes, occasionally more) for Earth's elliptical orbit and axial tilt causing true solar noon to drift ahead of or behind clock noon through the year. It also computes a purely geometric horizon crossing and doesn't apply the standard atmospheric refraction / solar-disc correction that real sunrise/sunset tables use (roughly a -0.833° adjustment for how the atmosphere bends light and for the sun having a visible disc rather than being a point) -- that correction alone is typically worth several minutes and can be the largest single source of difference on a given day. And this calculator takes no longitude, so its clock times implicitly assume you sit on your time zone's central meridian, which can be off by up to roughly half an hour depending on where in the zone you actually are. Your phone's sunrise/sunset time also folds in your specific time zone and daylight saving offset, none of which this calculator's solar times include.

No -- it depends entirely on the season. In northern summer, higher northern latitudes get progressively longer days than latitudes closer to the equator, up to midnight sun near the pole. In northern winter, that relationship reverses: higher northern latitudes get progressively shorter days, down to polar night near the pole. There's no single latitude-to-daylight direction that holds year-round.