Sun Path & Shadow Planner — Local Coordinates and Obstruction Study
Calculate daily direct-sun intervals and ground shadows from manually entered coordinates and obstacles, with downloadable diagrams and a time-by-time CSV.
Sunpath Studio
Choose your inputs, or load the working example to explore the result. Your files stay on this device.
Your inputs
Required fields are marked with an asterisk.
Your result
Review your output, then save it to your device.
Make the next step clear.
Your findings, assumptions and next steps will appear here after you run the check.
Sunpath Studio · https://sunpath.kitforma.com/ · KitForma
Runs locally in your browser
Download actual usable output
Explicit assumptions and supported inputs
Understand the evidence.
Focused guides explain the rules, the edge cases and the checks worth doing before you act.
Set coordinates and clock time for a sun-path study
A correct date and UTC offset are as important as the scene.
Read the guide ↗Field guide / 02Build a useful manual obstruction scene
Simple measured boxes can answer bounded shade questions.
Read the guide ↗Field guide / 03Read direct-sun hours without overstating accuracy
Sampling, weather and illuminance are separate questions.
Read the guide ↗Before you start
Do I need a paid map API?
No. Enter coordinates and simple obstacle geometry manually; all calculations run locally.
Does this calculate energy yield or indoor lux?
No. It calculates geometric solar direction, direct obstruction and ground shadows.
Does it handle daylight-saving time?
You enter the correct UTC offset for the selected date, including daylight-saving time.
Can I model rotated walls or trees exactly?
No. Obstacles are opaque axis-aligned boxes on flat ground. Approximate only where that is useful and disclose the simplification.
Why do sunrise times differ slightly from another service?
This calculation uses a simplified solar ephemeris and a geometric horizon, without atmospheric refraction. Daily totals also use ten-minute samples.
Sources & assumptions
Formats, algorithms and supported features are documented below. Check the stated scope and inspect your output before using it.
- SunCalc calculation source ↗
Published low-order solar-position equations and angle conventions.
- NOAA calculation details ↗
Solar-angle assumptions and atmospheric/time-zone limitations; NOAA notes the calculator is no longer actively maintained.
- Andrew Marsh shading model ↗
Browser-based geometric obstruction studies and their scope.
Reviewed 2026-10-17. Read our methodology or report an issue.