House Sunlight Calculator
Check direct sunlight at a house window, garden or patio. See morning and afternoon hours, compare months and model nearby obstructions.
One house. Different light at every point.
- 1 · Find your houseSearch above, then place the observer at a window.
- 2 · Set the scene
- 3 · Read your hoursSee morning, afternoon and monthly results ↓
Studying a patio or garden instead? Use an outdoor receiving point →
Solar times, the sky view and date controls remain available.
Light on this day
Europe/Lisbon · Select any event to move the map to that instant. Times are displayed to the minute; selection keeps the calculated instant.
Sunrise and sunset use an open horizon and atmospheric refraction. Dawn/dusk use the sun’s center at −6°, −12° and −18°. Golden light uses −4° to +6°: a planning convention, not a weather forecast. Calculation notes →
FROM DIRECTION TO DURATION
When does direct sunlight reach here?
2026-09-18 · Lisbon, Portugal · Europe/Lisbon
Each bar shows direct sun within that local clock hour. Clock changes can skip or repeat an hour; repeated-hour totals may exceed 60 minutes.
Read hourly values
| Local hour | Direct sun |
|---|---|
| 00:00 | 0 h 00 m |
| 01:00 | 0 h 00 m |
| 02:00 | 0 h 00 m |
| 03:00 | 0 h 00 m |
| 04:00 | 0 h 00 m |
| 05:00 | 0 h 00 m |
| 06:00 | 0 h 00 m |
| 07:00 | 0 h 00 m |
| 08:00 | 0 h 00 m |
| 09:00 | 0 h 00 m |
| 10:00 | 0 h 00 m |
| 11:00 | 0 h 00 m |
| 12:00 | 0 h 52 m |
| 13:00 | 1 h 00 m |
| 14:00 | 1 h 00 m |
| 15:00 | 1 h 00 m |
| 16:00 | 1 h 00 m |
| 17:00 | 1 h 00 m |
| 18:00 | 1 h 00 m |
| 19:00 | 0 h 36 m |
| 20:00 | 0 h 00 m |
| 21:00 | 0 h 00 m |
| 22:00 | 0 h 00 m |
| 23:00 | 0 h 00 m |
Show direct-sun time windows (1)
- 12:08 WEST–19:36 WEST
Clear-sky geometry, not a weather forecast. Two-minute sampling; time-window edges are approximate. Sun must face the selected window. 0 modeled obstacles; no terrain horizon loaded. Missing geometry is not proof of an unobstructed site.
What reaches your window?
Facing direction changes when direct sunlight can enter. The floor reach below uses your window height and sill.
Illustrative 8 m deep room. The far edge uses sill + window height. Width affects the patch’s width, not this distance; furnishings and overhangs are not included.
| Date | Direct sun | Explore date |
|---|---|---|
| march Equinox2026-03-20 | 7 h 26 m | |
| june Solstice2026-06-21 | 8 h 02 m | |
| september Equinox2026-09-23 | 7 h 24 m | |
| december Solstice2026-12-21 | 6 h 50 m |
Two-minute midpoint samples. 0 modeled obstacles. Counts sunlight facing the window. Clear-sky geometry, not a weather forecast.
A different season. A different light.
Keep your place and jump through the year.
Find your alignment.
Choose what you want to see from Lisbon, Portugal.
1 Choose your target
The pin is where you stand. Mark the landmark or direction you want the sun to line up with.
2 Choose the light
Set precise angles and tolerance
3 Pick your date range
Select a map target first, or open precise angles to enter a direction.
The target sets a compass direction, not the height of a landmark. Windows show when the Sun’s center is within the selected angular tolerance. Terrain, buildings and weather are not included in this alignment search. Near-horizon geometry is not a guarantee of a visible sunrise.
How Much Sun Does My House Get? Free Calculator
A house does not have one sunlight total. Start with a receiving point: a window, a balcony or a place in the garden. This house study starts with a vertical window; choose the garden tool for an outdoor point.
Use this when: You are comparing direct sunlight at a particular house window before choosing a room, layout or property.
What this tool calculates
- Direct-sun time windows for a selected window-facing point
- Morning and afternoon direct-sun duration
- Twelve representative dates across the year
- Idealized window floor reach
How to use it
- 01
Locate your house
Search for the address, then place the observer at the window being studied. An address marker is not a measured window location.
- 02
Set the window direction
Choose the outward-facing compass bearing under Your study. Edit your scene to set the receiving height and window dimensions.
- 03
Add the surroundings
Add measured obstacles or inspect available building heights and terrain in Context. Missing geometry is not clear sky.
- 04
Read the sunlight hours
Use the direct-sun windows and morning/afternoon totals. Explore sunlight by month to compare the 15th of each month, not monthly averages.
How to read the result
Read the model, then check the place
The result applies to one modeled receiving point, not every room or the whole property.
Keep the assumptions with the result
Save the scene and export a field sheet to retain coordinates, time zone and the modeled geometry.
Limits you should know
- The result applies to one modeled receiving point, not every room or the whole property.
- Direct sunlight is not total room brightness. Diffuse daylight, glazing, window recesses, furnishings and overhangs are not fully modeled.
- Time windows use two-minute samples. Monthly representative days use five-minute samples.
Questions about this calculator
How much sun does my house get?
There is no single accurate number for a whole house. Choose a window or an outdoor point, specify its geometry and inspect the modeled direct-sun hours for that date. Repeat for other rooms and seasons.
Why can a bright room have few direct-sun hours?
A room can receive diffuse skylight or reflected light without a direct solar ray through the window. This calculator estimates direct sun, not total indoor brightness or lux.
Can I compare sunlight before buying a house?
You can compare modeled points with saved scenes and the same dates. Check window direction, receiving height and nearby obstacles at each property; incomplete map data is not a site survey.
Methodology version 2.0 · Reviewed September 20, 2026