Distance in Miles:

Viewer height in Feet:

Distance = ?, View Height = ? Radius = ?

Results ignoring refraction

Horizon = ?

Bulge =

Drop =

Hidden=

Horizon Dip =

With Standard Refraction 7/6*r, radius = ?

Refracted Horizon = ?

Refracted Drop= ?

Refracted Hidden= ?

Refracted Dip =

"Standard Refraction" is an approximation of the refraction expected under average or Standard Atmospheric conditions.

Actual atmospheric conditions can vary, and the resultant refraction can be complex, especially close to the horizon.

See here for the source of this approximation. See here for historical usage of this approximation

The image below is interactive, you can drag the three blue dots , zoom and move. It illustrates the relationship between the various numbers, not the actual values.