Area and perimeter of a regular polygon

A regular polygon (n-gon) is a figure with n edges of equal lengths.

polygon

a	edge
C	circumcircle
c	incircle
R	radius (circumcircle)
r	radius (incircle)
O	center

Calculator

Select the units of measurement

Enter the number of edges

number of edges

n =

Enter 1 value

edge

a =

circumcircle (radius)

R =

incircle (radius)

r =

area

A =

perimeter

P =

Error

Round to decimal place

Calculation procedure

Formulas

polygon

n	number of edges

area

$$ A = \frac{1}{4} n a^2 \cot\frac{180^\circ}{n} $$

perimeter

$$ P = n \cdot a $$

circumcircle (radius)

$$ R = \frac{a}{2 \cdot\sin\frac{180^\circ}{n}} $$

incircle (radius)

$$ r = \frac{a}{2 \cdot\tan\frac{180^\circ}{n}} $$

Area and perimeter of a regular polygon

polygon

Calculator

Select the units of measurement

Enter the number of edges

number of edges

Enter 1 value

edge

circumcircle (radius)

incircle (radius)

area

perimeter

Error

Calculation procedure

Formulas

polygon

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