Sunrise & Sunset Calculator

This tool tells you the exact sunrise, sunset, solar-noon and day-length for any place on any date. Pick an Indian city from the list or switch to Custom and type a latitude/longitude, set the date, and read the times off instantly. Sunrise and sunset depend on three things: where you are (latitude and longitude), what day of the year it is (which fixes the sun's declination), and your time zone. The calculator combines all three using the NOAA Solar Position Algorithm — the same astronomical model behind NOAA's public solar calculator — and is accurate to within ±1 minute for civilian use across the years 1900-2100.

It is built for everyday Indian needs: planning a pre-dawn jog or namaz/sandhya before office, timing photography during the golden hour, knowing the iftar and sehri window during Ramzan, scheduling agricultural or solar-panel work around daylight, working out how much daylight is left for a road trip, or simply settling the perennial argument about whether the sun really rises at 6 o'clock.

How the calculation works

Internally the algorithm converts your date to a Julian Day number, then derives the sun's mean longitude and mean anomaly. It applies the equation of centre to get the true longitude, corrects for nutation and aberration, and from that computes two key quantities: the solar declination (how far north or south of the equator the sun sits that day, swinging between +23.5° at the June solstice and -23.5° at the December solstice) and the Equation of Time (the seasonal mismatch between sundial time and clock time). Using your latitude and the declination it solves the hour-angle equation for the moment the sun's upper limb crosses a solar zenith of 90.833°. Sunrise is then solar noon minus half the day length, and sunset is solar noon plus half the day length.

What "sunrise" means here

The standard civilian definition is used: the moment the upper limb of the sun appears to touch the horizon. That corresponds to a solar zenith of 90.833° — the 90° geometric horizon plus a combined 0.833° correction for atmospheric refraction (about 0.566°) and the sun's angular radius (about 0.267°). Refraction bends light from below the horizon up to the observer, so the disc's upper edge is already visible while its centre is still geometrically below the horizon. Civil twilight — the softer light when the sun is up to 6° below the horizon — begins earlier and is brighter than this sunrise instant, which is why the sky is usable for outdoor work before the disc itself appears.

Why solar noon is almost never 12:00

Two effects move solar noon away from clock noon. The first is the longitude correction inside your time zone: every degree you sit east of the zone's reference meridian moves solar noon four minutes earlier, and every degree west moves it four minutes later. India uses a single time zone with reference meridian 82.5°E, so Mumbai (~73°E) sees solar noon around 12:40 while Kolkata (~88°E) sees it around 11:55 — a gap of roughly 45 minutes across one country. The second effect is the Equation of Time, a seasonal ±15-minute offset caused by earth's elliptical orbit and the 23.5° axial tilt.

Worked example — Mumbai, 21 June

Take Mumbai (19.07°N, 72.88°E) on 21 June, the summer solstice, with India's timezone offset of +5.5. On that date the solar declination is near its maximum of +23.4°, so the sun's path is high and the day is long — about 13 hours 17 minutes. Because Mumbai sits roughly 9.6° west of the 82.5°E reference meridian, solar noon falls about 38 minutes after clock noon, around 12:38, and on the solstice the Equation of Time is a small negative value that nudges it a touch earlier. Sunrise works out to roughly 06:00 and sunset to roughly 19:17. Run the same date for Delhi (28.6°N) and you will see a noticeably longer day — close to 13 hours 50 minutes — because the higher latitude lengthens the summer day.

Tips

• For the most accurate result for your exact spot, use Custom and paste your latitude/longitude (you can copy these from any map app) instead of picking the nearest big city.
• Remember north latitude is positive and east longitude is positive — every Indian location uses positive values for both.
• Leave the timezone at 5.5 for anywhere in India; change it only if you are computing times for another country.
• For golden-hour photography, aim for the 30-40 minutes just after the sunrise time or just before the sunset time shown.

Common mistakes

• Assuming a fixed 6 AM / 6 PM. Only near the equinoxes and near the equator is the day close to a clean 12 hours; in north India the summer and winter times differ by well over an hour.
• Confusing solar noon with 12:00. They can differ by 45 minutes or more in India because of the single national time zone.
• Expecting these to match a Panchang to the second at altitude. Times here assume sea level; high-altitude locations (above ~1000 m) can see sunrise 1-3 minutes earlier than computed.
• Entering longitude as negative for India. India is east of Greenwich, so longitude is positive.

Downstream uses

The astronomical sunrise computed here is the same value used by Drik / Vedic Panchang calculations (Tithi-day boundaries, Rahu Kaal proportional segments, Choghadiya muhurats, Karva Chauth moonrise tables). All the Panchang tools in this section import this same compute function, so the times line up across the site.