Global sunlight and shadow planning
See where sunlight will reach before the day arrives.
Place an exact point, choose a date, add the buildings, walls, or trees you can verify, and watch direct sun and shade move across the map, window, balcony, or garden.
- Any valid coordinate
- Saved in your browser
- Assumptions stay visible
Loading the global map…
Click once to move the receiving point.
Plan for the light you will actually get.
Mark the exact spot, aim the receiving surface, add what blocks the sky, then move through the day.
- 01
Place the point
Pin a window, balcony, room, or patch of ground.
- 02
Aim the space
Set the direction it faces with the map or compass control.
- 03
Add obstructions
Place nearby buildings, walls, and trees, then enter verified dimensions.
- 04
Watch the day
Scrub any date and time to see direct light and shadow move.
One sun model.
Many real decisions.
Explore every tool 
Useful estimates, without false precision.
SunCarta calculates the sun from your coordinates, date, and time, then projects the obstacles you can verify. Every result separates calculated solar geometry from estimated scene geometry.
- Solar geometry
- Position is calculated from latitude, longitude, date, local time, and time zone.
- Verified obstructions
- Buildings, walls, and trees use the positions and dimensions you add against the map context.
- Visible confidence
- Coverage, assumptions, and important limits stay beside the result.
- Local-first projects
- The current setup stays in browser storage unless you clear or reset it.
Core references: NOAA solar calculations · OpenStreetMap contributors · IANA time zones
Before you trust a shadow
How accurate is SunCarta?
Solar position is deterministic for the selected coordinate, date, time, and time zone. A shadow estimate is only as accurate as the obstacle height, width, and position supplied, so SunCarta keeps those assumptions visible.
Can it account for trees?
Yes. Add a tree, set its height, crown width, and opacity, then compare relevant dates. Tree shade remains an estimate because foliage changes by species, pruning, weather, and season.
Does it work anywhere in the world?
The solar calculation works for any valid latitude and longitude. Map and address coverage vary by data provider, and polar day or night is reported without inventing sunrise or sunset times.
Are my saved locations private?
The active project is stored in your browser by default and the simulator does not require an account. A submitted place search is sent through SunCarta’s configured geocoding service; map clicks and direct coordinate entry do not require an address search.
Can I compare two homes?
Use the same dates, orientation method, and obstacle assumptions for each home, recording the results before moving the point. The current release stores one active setup at a time; it does not yet claim a side-by-side comparison report.