Sunrise & Sunset Calculator
Enter any latitude and longitude to calculate exact sunrise, sunset, and solar noon times. Uses astronomical algorithms accurate to within 1 minute.
How This Calculator Works
This calculator uses the SunCalc library by Vladimir Agafonkin, which implements the astronomical algorithms from Jean Meeus' book "Astronomical Algorithms" (1991). The same algorithms are used by professional observatories and astronomical institutions worldwide.
Calculations incorporate atmospheric refraction (0.833 degree correction) at the horizon, which accounts for the way Earth's atmosphere bends light near the horizon. This is why the sun appears above the horizon for a brief moment before it actually rises geometrically.
Accuracy
The calculator is accurate to within 1 minute for most locations below 70 degrees latitude. For polar regions (above 70 degrees), accuracy may decrease. You can verify results against the US Naval Observatory for your location.
What You Can Calculate
Enter any latitude (from -90 to +90) and longitude (from -180 to +180) to get: sunrise time, sunset time, solar noon, total daylight duration, and golden hour windows. The calculator uses your device's local timezone for display, or you can enter coordinates manually for any location worldwide.
Frequently Asked Questions
- How accurate is this sunrise calculator?
- Within 1 minute for most locations below 70 degrees latitude. Results use Jean Meeus astronomical algorithms, the same standard used by professional observatories.
- How do I find my latitude and longitude?
- Click "Use My Location" for automatic detection. Or search your city on any map service, right-click, and read the coordinates shown.
- What algorithm does this calculator use?
- The SunCalc library (Vladimir Agafonkin) implementing Jean Meeus astronomical algorithms, accurate for all dates from 1900 to 2100.
- Does sunrise time change every day?
- Yes, by 1 to 3 minutes per day near equinoxes, and almost no change near solstices. This is caused by Earth's elliptical orbit and axial tilt.