Sun Position & Solar Angle Calculator
Calculate live solar azimuth, solar altitude angle, shadow length, and sun tracking paths for solar panel optimization, photography, and architecture.
The Sun Position Calculator computes real-time solar elevation (altitude above horizon) and azimuth (compass direction from North) for any latitude, longitude, and timestamp on Earth. It includes an interactive solar path visualizer and shadow length multiplier for solar panel alignment, architectural lighting, and photography.
Below Horizon (Night)
Compass angle from True North
Sun below horizon
Sun latitude on celestial sphere
Daily Solar Milestones (9/20/2026)
Sun Position Technical Specifications & Standards
WGS84 / Topocentric Horizontal Coordinate System
Standard global ellipsoidal coordinate reference system
Topocentric Geodesics
Sub-arcminute angular precision
GeoJSON · KML · CSV · SVG
Compatible with QGIS, ArcGIS, Google Earth & CAD
100% Client-Side
Calculations run in-browser. Zero coordinate logging.
How to Use the Sun Position & Solar Angle Calculator
Follow this step-by-step procedure to execute precise spatial measurements and export results.
- 1Set coordinates: Enter latitude/longitude or search your city.
- 2Choose date & time: Select live current time or pick a specific date and hour.
- 3Read solar altitude: Inspect the sun vertical angle in degrees above the horizon.
- 4Check azimuth & shadow: View the 360° compass bearing and the shadow length multiplier ratio.
Geodesic Precision vs. Competitor Mapping Approaches
Most legacy mapping utilities (such as CalcMaps and FreeMapTools) rely on planar Web Mercator projections or spherical approximations, causing significant mathematical distortion at higher latitudes. GeoMap Suite computes exact ellipsoidal geodesics on the WGS84 reference ellipsoid.
| Calculation Model | Mathematical Basis | Distortion on WGS84 | Standard Tools | Practical Application |
|---|---|---|---|---|
| Planar (Web Mercator) | Cartesian dx² + dy² | 10% to 200%+ error | CalcMaps / Simple map tools | Distorts drastically away from equator. Inaccurate for true distance. |
| Spherical Great-Circle | Haversine (R = 6,371 km) | Up to 0.5% (~5 km/1,000 km) | Basic Google Maps wrappers | Ignores Earth's polar flattening. Reasonable for rough estimates. |
| GeoMap Suite Ellipsoidal | Karney Direct/Inverse WGS84 | < 15 nanometers (<0.0001%) | GeoMap Suite | Geodetic surveying, maritime, flight paths & legal boundary analysis. |
Worked Example: Solar Elevation Angle at Solar Noon in Phoenix, AZ
A solar installer evaluates panel tilt for a rooftop installation on the vernal equinox.
Input Parameters
- Location
- 33.4484° N, 112.0740° W (Phoenix, AZ)
- Date
- March 21 (Equinox), 12:35 PM
Computed Outputs
- Solar Altitude
- 56.55°
- Solar Azimuth
- 180.00° (Due South)
- Optimal Solar Panel Tilt
- 33.5° facing South
Step-by-Step Mathematical Process
- Calculate solar declination: 0.0° (Sun over equator).
- Calculate solar noon altitude: 90° - Latitude = 90° - 33.45° = 56.55° above horizon.
- Calculate shadow ratio: 1 / tan(56.55°) = 0.66× object height.
Understanding Your Results & Practical Interpretation
Solar Azimuth vs. Altitude
Altitude is the vertical angle (0° at the horizon to 90° directly overhead at zenith). Azimuth is the horizontal compass angle (0° = North, 90° = East, 180° = South, 270° = West).
Practical Applications & Real-World Use Cases
Rooftop Solar Design
Optimize photovoltaic panel azimuth and seasonal tilt angles.
Architectural Daylight Studies
Model seasonal window glare and building shadow casts.
Mathematical Methodology & Geodetic Accuracy
Topocentric Celestial Coordinates (VSOP87 Ephemeris)
Computes right ascension and declination using high-order planetary perturbation series, transforming into horizontal local topocentric coordinates.
sin(h) = sin(φ)sin(δ) + cos(φ)cos(δ)cos(H); cos(A) = (sin(δ) - sin(φ)sin(h)) / (cos(φ)cos(h))Limitations & Boundary Conditions
- •Assumes sea-level horizon; does not account for local topography or structural shading.
Authoritative Reference Standards
Troubleshooting & Geographic Edge Cases
Why is the shadow length ratio null at night?
When the sun is below the horizon (altitude <= 0°), sunlight does not reach the ground, so no shadow is cast.
Frequently Asked Questions
Solar elevation (altitude) is the vertical angle of the Sun measured in degrees above the horizon (from 0° at the horizon to 90° at zenith). Solar azimuth is the horizontal compass direction of the Sun, measured in degrees clockwise from True North (0° = North, 90° = East, 180° = South, 270° = West).