# Angular Size (Diameter) Calculator

The angle of how large a circle appears from a given point is the angular size or diameter which can be calculated based on the distance between the observer and the object, linear size.

## Calculate Angular Size (Diameter) using Distance and Linear Size

The angle of how large a circle appears from a given point is the angular size or diameter which can be calculated based on the distance between the observer and the object, linear size.

Code to add this calci to your website

#### Formula:

α=2*arctan(d/(2*L))
**Where,**
α = Angular Diameter
d = Linear Size
L = Distance to Object