Calculate sunrise, sunset, day length, and civil twilight for any location and date. Includes monthly sunrise/sunset table and polar day/night detection.
Sunrise and sunset times depend on your geographic location, the date, and atmospheric refraction. At the equator, day length varies little throughout the year — about 12 hours year-round. But at higher latitudes, the difference is dramatic: London ranges from 8 hours in December to 16.5 hours in June. Beyond the Arctic/Antarctic circles, entire days of continuous sunlight (midnight sun) or darkness (polar night) occur.
The calculation involves solar declination (the sun's north-south position, ±23.45° over the year), the observer's latitude, and the equation of time (which accounts for orbital eccentricity and axial tilt). Atmospheric refraction lifts the apparent sun by about 0.83° at the horizon, adding a few minutes to visible daylight.
This calculator provides sunrise, sunset, solar noon, day length, and civil twilight times for any location on Earth. The monthly table lets you see how daylight varies through the seasons — essential for planning outdoor activities, agriculture, photography, and solar energy systems.
Knowing sunrise and sunset is essential for photographers (golden hour), gardeners (frost timing), outdoor enthusiasts, pilots, and anyone planning activities around natural light. The monthly table reveals seasonal patterns at a glance.
This tool is designed for quick, accurate results without manual computation. Whether you are a student working through coursework, a professional verifying a result, or an educator preparing examples, accurate answers are always just a few keystrokes away.
Hour angle at sunrise: cos(H₀) = −tan(φ)tan(δ), where φ = latitude, δ = solar declination. Sunrise = solar noon − H₀/15. Sunset = solar noon + H₀/15. Day length = 2H₀/15 hours.
Result: Sunrise: 05:25, Sunset: 20:31
New York on June 21: day length ≈ 15 hours 6 minutes. Solar noon at 12:58 PM EDT (sun is south of true south due to equation of time correction).
Use consistent units throughout your calculation and verify all assumptions before treating the output as final. For professional or academic work, document your input values and any conversion standards used so results can be reproduced. Apply this calculator as part of a broader workflow, especially when the result feeds into a larger model or report.
Most mistakes come from mixed units, rounding too early, or misread labels. Recheck each final value before use. Pay close attention to sign conventions — positive and negative inputs often produce very different results. When working with multiple related calculations, keep intermediate values available so you can trace discrepancies back to their source.
Enter the most precise values available. Use the worked example or presets to confirm the calculator behaves as expected before entering your real data. If a result seems unexpected, compare it against a manual estimate or a known reference case to catch input errors early.
It is approximately — sunrise to solar noon equals solar noon to sunset. But "12 hours from sunrise" is not meaningful; day length determines the gap between the two events.
When the sun never sets — occurs inside the Arctic/Antarctic circles during their respective summers. At the North Pole, the sun stays above the horizon for 6 months continuously.
Time zones cover 15° of longitude but your location may be offset. Also, the equation of time adds up to ±16 minutes of correction from Earth's orbital mechanics.
Within ±2 minutes for most locations. It uses the standard astronomical formulas but omits altitude correction and precise atmospheric refraction, which add ~1 minute of precision.
Yes — higher elevation means you can see farther over the horizon, advancing sunrise by a few minutes. This calculator assumes sea level.
A correction (±16 minutes) for Earth's elliptical orbit and axial tilt that makes solar noon shift relative to clock noon through the year, forming the analemma pattern. Understanding this concept helps you apply the calculator correctly and interpret the results with confidence.