Sun position calculator
Altitude measures how high the Sun is above your geometric horizon. Azimuth measures its compass bearing clockwise from north: east is 90°, south 180° and west 270°.
At 2026-03-20 12:00 UTC, the Sun is above the geometric horizon at 51.4779°, 0°.
What does the shadow measure?
For an upright of height h on horizontal ground, shadow length is h ÷ tan(altitude). Its bearing points 180° away from the Sun. Below the horizon there is no direct-Sun shadow; at the zenith the shadow contracts to zero and its direction becomes indeterminate.
When is the Sun highest?
The highest altitude occurs around local solar noon, which is not always 12:00 on a civil clock. Changing longitude shifts the Sun’s position at the same UTC instant; changing latitude changes the path’s height.
A negative altitude means the Sun’s centre is below the geometric horizon. Terrain and atmospheric refraction can change the visible sunrise or sunset.
Use a noon shadow to compare two places →