Sunrise, Sunset & Golden Hour Calculator

About the Sunrise, Sunset & Golden Hour Calculator

Find the times of sunrise and sunset, solar noon, civil, nautical and astronomical twilight, the photographers’ golden hour and blue hour, and the length of the day — and how much it changed since the day before — for any place on Earth and any date from 1600 to 2400. Pick one of about 2,000 cities (every Indian city of 100,000 people or more and the world’s large cities), let your browser share your location, or type coordinates; times are shown in the place’s own time zone, with daylight saving time applied.

A timeline shows the whole day from midnight to midnight, a table lists the month (and downloads as CSV), and a chart follows the day length through the year with the dates of the equinoxes and solstices. The calculator handles the midnight sun and the polar night, and the white nights when twilight never ends. Everything is computed in your browser with the astronomy-engine library, using the US Naval Observatory’s definitions.

Common uses

• Planning photography for the golden or blue hour, and knowing where on the horizon the Sun will rise or set.
• Scheduling travel, treks and outdoor events to finish before dark.
• Astronomy and stargazing: when astronomical twilight ends and the sky is fully dark.
• Sailing and aviation briefings that use nautical or civil twilight.
• School geography and physics projects on day length, latitude and the seasons.

Definitions used

• Sunrise and sunset: the moment the upper edge of the Sun touches a level, unobstructed horizon. For the calculation the Sun’s centre is 50′ below the horizon: 16′ for its radius plus 34′ of average atmospheric refraction (USNO).
• Solar noon: the Sun crosses the meridian and is highest in the sky.
• Civil, nautical and astronomical twilight: begin in the morning and end in the evening when the centre of the Sun is 6°, 12° and 18° below the horizon (no refraction). Civil twilight is bright enough for most outdoor activities; during nautical twilight the horizon is still visible at sea; after astronomical twilight the sky is fully dark.
• Golden hour and blue hour: photographers’ conventions without an official definition. Here golden hour is while the Sun is between 4° below and 6° above the horizon, and blue hour while it is between 6° and 4° below.
• Day length: sunset minus sunrise. On the day the midnight sun begins or ends — a sunrise without a sunset, or the other way round — it is the time the Sun is up within that date.

Why the times can differ from what you see

The times assume sea level, a flat horizon and average air. Hills, buildings or a sea horizon seen from a height shift what you observe, and refraction changes with temperature and pressure, so real sunrise and sunset can differ by a minute or more — and by many minutes near the polar circles, where the Sun crosses the horizon at a shallow angle (USNO). Times are rounded to the nearest minute.

At high latitudes a calendar day may have no sunrise or sunset at all. When the Sun stays up the tool says midnight sun; when it stays down, polar night, with any twilight around noon — and it tells you when the Sun next sets or rises. A sunset after midnight is marked “+1 day”.

Earliest sunset is not on the shortest day

Because the Earth’s orbit is elliptical and its axis tilted, solar noon drifts by up to about a quarter of an hour over the year (the equation of time). So the earliest sunset comes before the December solstice and the latest sunrise after it. In New Delhi in 2026 the shortest day is 22 December (10 h 19 min), but the earliest sunset is around 2 December (17:24) and the latest sunrise around 11 January (07:15). The longest day is 21 June (13 h 58 min).

Sources

• US Naval Observatory, Astronomical Applications Department, Rise, Set, and Twilight Definitions — and its “Complete Sun and Moon Data for One Day” service, which this tool’s tests compare against for Delhi, London, Sydney, New York, Tromsø and Reykjavík (all within a minute).
• D. Cross, astronomy-engine (MIT licence): positions of the Sun and the searches for rise, set, altitude and meridian crossings, the seasons and Earth’s perihelion and aphelion; the library is tested against JPL Horizons and NOVAS.
• J. Meeus, Astronomical Algorithms, 2nd ed.: the underlying methods, also used by NOAA’s Solar Calculator.
• GeoNames (CC BY 4.0): city names, coordinates and time zones of the place search; the IANA time zone database built into your browser for daylight saving time.

Limitations

• Times are for sea level and a level horizon; mountains, buildings or your height above the ground are not taken into account.
• Refraction is the standard average value; unusual weather can shift sunrise and sunset by a minute or more, much more near the poles.
• Golden and blue hour are conventions — the actual light depends on clouds, haze and the scene.
• The city list is GeoNames’ larger places plus some well-known sunrise and sunset spots; for villages, a beach or a peak use “Use my location” or type coordinates.
• Typed coordinates take the time zone of the nearest listed city within 300 km, otherwise the nautical zone of the longitude (one hour per 15°). Near a border or at sea check the zone in Coordinates and time zone and change it if needed.
• Dates are limited to the years 1600–2400; historical dates use the time zone rules of the IANA database, which before about 1970 can differ from what clocks actually showed.

Privacy

Everything is calculated in your browser. If you press “Use my location”, your browser asks for permission and the coordinates are used on this page only — they are not sent to MySmartCoPilot or anyone else. The last city or coordinates you chose (never your device’s position) are remembered in this browser for next time; Reset forgets them.