Inradius of Regular Polygon given Circumradius Calculator

Calculate Inradius





Formula

The formula to calculate the Inradius of a Regular Polygon is:

\[ r_i = r_c \cdot \cos\left(\frac{\pi}{N}\right) \]

Definition

The inradius of a regular polygon is the distance from the center of the polygon to the midpoint of one of its sides. The circumradius is the radius of the circumcircle that touches each vertex of the polygon. The number of sides is the total number of sides of the polygon.

Example Calculation

Let's assume the following values:

Using the formula:

\[ r_i = 13 \cdot \cos\left(\frac{\pi}{8}\right) \approx 12.0104 \]

The Inradius is approximately 12.0104 Meters.

Conversion Chart

Circumradius (Meters) Number of Sides Inradius (Meters)
12 8 11.086554390135440
12.5 8 11.548494156391085
13 8 12.010433922646728
13.5 8 12.472373688902371
14 8 12.934313455158014