Sunrise and sunset times

How the times are calculated

For each day the page finds the Sun's position with the same equations the U.S. National Oceanic and Atmospheric Administration (NOAA) publishes for its solar calculator: the Sun's declination and the “equation of time”, which together give the moment of solar noon and how far the Sun travels between the horizon and its highest point. Sunrise and sunset are when the Sun's centre is 0.833° below the horizon; civil dawn and dusk when it is 6° below. Everything runs in your browser.

The times assume a flat horizon at sea level. On a mountain top you see the Sun earlier and later; in a valley or between tall buildings, later and earlier. Unusual air temperature near the ground can bend light enough to shift sunrise by a minute or two.

Day length through the year

At the equator the day is close to 12 hours all year. Further from it, the difference between summer and winter grows: London gets about 16½ hours of daylight in June and under 8 in December, while Sydney has its longest days in December. Day length changes fastest around the March and September equinoxes — in London by nearly four minutes a day — and hardly at all near the solstices.

The equinoxes are not quite the days of equal day and night. Because sunrise and sunset are measured from the Sun's top edge and refraction lifts the Sun, “day” is a few minutes longer than “night” on the equinox itself; the day with 12 hours of daylight comes a few days before the March equinox and after the September one.

Questions and answers

What exactly is sunrise?

The moment the top edge of the Sun appears on a flat, sea-level horizon. Because the atmosphere bends light, the Sun is actually about half a degree below the horizon at that moment; the standard calculation uses a solar depression of 0.833° to allow for refraction and the Sun's radius.

What is civil twilight?

The time when the Sun is less than 6° below the horizon. Before civil dawn and after civil dusk you usually need artificial light outdoors; in between there is enough light for most activities. Many countries use civil twilight in rules for vehicle lights.

Why are the earliest sunrise and the longest day on different dates?

Because of the equation of time: the Earth's tilted axis and elliptical orbit make solar noon drift earlier and later through the year. In mid-northern latitudes the earliest sunrise comes about a week before the June solstice and the latest sunset about a week after.

How accurate are these times?

We checked the calculation against the U.S. Naval Observatory for twelve places, including polar and southern-hemisphere cities and daylight-saving change days: the differences were two minutes or less. Hills, buildings and air temperature change what you actually see by more than that.

Do you use my location?

No. You choose a city from the list; the page never asks for your position, and the choice is only remembered in your browser's own storage.

What happens near the poles?

Above the Arctic Circle the Sun stays up for weeks around the June solstice and stays below the horizon around the December solstice. The table then says “no sunset” or “no sunrise” and shows 24 or 0 hours of daylight.

For planning and curiosity, not for navigation or safety-critical use. The moon phase for any day is on the moon phase page.