Sunrise & Sunset Calculator

For your location (detected by the browser, or any city you enter) and any date, the page gives sunrise, sunset, solar noon, day length, and the twilight times: civil twilight, when there is still enough light to work outside; nautical, when the horizon is just visible at sea; and astronomical, after which the sky is fully dark. It also shows the golden hour, the period just after sunrise and before sunset when the low sun gives warm, soft light, and the blue hour of deep blue sky before sunrise and after sunset. The calculation uses the standard solar position algorithm and is accurate to within a minute or two; local hills, buildings and refraction on the day account for the rest.

At the equator day length barely changes: about 12 hours all year. At 41° N (Istanbul, New York, Madrid) it ranges from roughly 9 h 20 m at the December solstice to 15 h at the June solstice. At 60° N (Oslo, Helsinki, St Petersburg) the range is 6 to 19 hours, and above the Arctic Circle the sun does not set for part of the summer or rise for part of the winter. The change is fastest around the equinoxes in March and September (three to four minutes a day at mid-latitudes) and slowest around the solstices. Solar noon, when the sun is highest, is rarely at 12:00 by the clock: time zones are wide and daylight saving shifts it by an hour, so in summer solar noon in western Spain is after 14:00.

• Photography. Plan a shoot for the golden hour; the page gives the exact window for the date, which in summer at high latitude can last over an hour and in the tropics only twenty minutes.
• Running, cycling and hiking. Know when you will need lights, and when a trail will be dark. Civil twilight, not sunset, is the practical limit for seeing your footing.
• Sleep and light exposure. Morning light anchors the body clock; check sunrise to time a walk. Our waking-up guide explains why. The alarm clock can be set to sunrise for the day.
• Fasting. Many traditions define fasting windows by dawn and sunset; the page gives both, but check the definition your community uses (some use nautical twilight for dawn).
• Solar panels and gardening. Day length and solar noon estimate available sunlight.

The moon phase page completes the picture for night-sky planning, and the world clock shows which of your contacts is in daylight right now.