Seasonal sunlight: how the sun enters your bedroom
The traditional advice to face south is really about daylight. Choose your city and window direction, then move the season and time to see where the sunlight falls on the floor.
How to read it
Feng shui favors south-facing rooms. In the northern hemisphere, a south window gets low winter sun that reaches deep into the room and high summer sun that stays near the window: warm in winter, cooler in summer. This tool draws that out.
Compare the patch of light with how far your bed is from the window. Morning sun on the bed tends to wake you; afternoon western sun in summer makes the room hotter.
We assume a window 1.5 m wide, with the sill at 0.9 m and the top at 2.1 m, and ignore buildings and trees outside, so this is the light on a clear day with nothing in the way.
Everything is calculated in your browser; nothing is uploaded. Sun position is accurate to about half a degree.