Solar Noon Calculator

About the Solar Noon Calculator

The Solar Noon Calculator finds the moment when the sun reaches its highest point for a given location and date.

Solar noon is not the same as 12:00 PM on the clock. It shifts with longitude, time zone choice, and the equation of time, so the local solar peak can fall before or after noon by several minutes. The calculator also reports sunrise, sunset, twilight, day length, and solar declination so you can see the full daylight window around that point.

That makes it useful whenever you need both the daily solar peak and the surrounding daylight times in one place.

When This Page Helps

Solar noon is the anchor point for a lot of daylight planning. Once you know where that peak lands, sunrise, sunset, and twilight are easier to interpret for photography, solar work, and general daylight planning.

How to Use the Inputs

1. Enter your latitude and longitude (or use a city preset).
2. Set the UTC timezone offset for your location.
3. Select a date or leave as today's date.
4. View solar noon, sunrise, sunset, and day length.
5. Check twilight times and the equation of time correction.
6. Explore how solar noon shifts throughout the year in the annual table.

Example Calculation

Tips & Best Practices

• Solar noon is latest (~12:45-1:05 PM) on the western edges of time zones.
• The longest day of the year is the summer solstice (~June 21 in Northern Hemisphere).
• Earliest sunrise doesn't coincide with the solstice — it's typically a week earlier.
• The analemma (figure-8 of sun positions at noon) is caused by the equation of time.
• At the equator, day length varies only ±15 minutes throughout the year.

The Equation of Time

The equation of time has two components: (1) the eccentricity of Earth's orbit causes the sun to appear to speed up and slow down relative to a perfect clock, and (2) the obliquity (tilt) of the ecliptic causes the sun's apparent motion along the celestial equator to be non-uniform even if Earth's orbit were perfectly circular.

These two effects combine to create the familiar figure-8 analemma. The maximum deviation is about +14 minutes in early February (sundial runs fast) and -16 minutes in early November (sundial runs slow).

Seasonal Daylight Patterns

At the equator, day length is nearly constant at 12 hours year-round. With increasing latitude, seasonal variation grows dramatically. At 45°N, the longest day is about 15.5 hours and the shortest about 8.5 hours. At the Arctic Circle (66.5°N), the sun doesn't set for at least one day at the summer solstice and doesn't rise for at least one day at the winter solstice.

Practical Applications

Solar panel installers use solar noon to determine the optimal azimuth (south-facing in the Northern Hemisphere). Solar declination determines the optimal tilt angle. Farmers and gardeners use day length to plan planting. Astronomers need astronomical twilight times to plan observations. And sundial enthusiasts need the equation of time to convert sundial readings to clock time.

Frequently Asked Questions

• Why isn't solar noon at 12:00 PM?

  Two reasons: (1) Your longitude within the time zone — time zones span 15° but use a single clock time, so locations east of the zone center see solar noon earlier than noon. (2) The equation of time — Earth's orbital eccentricity and axial tilt cause solar time to deviate from clock time by up to ±16 minutes.

• What is the equation of time?

  The difference between apparent solar time (sundial time) and mean solar time (clock time). It's caused by Earth's elliptical orbit (faster near perihelion) and the 23.45° axial tilt. The combined effect creates a figure-eight pattern called the analemma.

• What is solar declination?

  The angle between the sun's rays and Earth's equatorial plane. It ranges from +23.45° (summer solstice in Northern Hemisphere) to -23.45° (winter solstice). At 0° (equinoxes), day and night are approximately equal everywhere.

• What is golden hour?

  The period shortly after sunrise and before sunset when sunlight is warm, soft, and directional. Typically the first/last hour of sunlight. This calculator shows sunrise and sunset so you can plan golden hour shoots.

• How accurate are these calculations?

  Within 1-2 minutes for sunrise/sunset and solar noon. Professional astronomical calculators account for atmospheric refraction, observer elevation, and precise orbital elements, which can shift times by ±1 minute.

• What are the twilight types?

  Civil twilight: sun 0-6° below horizon (can read outdoors). Nautical twilight: sun 6-12° below (horizon still visible at sea). Astronomical twilight: sun 12-18° below (sky appears dark for astronomy).