Heptagon online calculator and formula

This function calculates various parameters of a regular heptagon, a polygon with 7 vertices.

To perform the calculation, select the required parameter in the menu and enter its value. Then click the 'Calculate' button.

Heptagon Calculator

Input

Argument Type

Value

Decimal places

Results

Side length a

Height h

Perimeter P

Area A

Diagonal e d

Diagonal f d

Outer circle radius ra

Inner circle radius ri

Properties

All sides are equal.

All angles are equal.

The bisector and heights all intersect at the center.

Formulas for the equilateral heptagon

Diagonal \(e\)

\(\displaystyle e = \frac{a}{2·sin(π/2/7)} \)

Diagonal \(f\)

\(\displaystyle f = 2 · a · cos\left( \frac{n}{7}\right) \)

Height \(h\)

\(\displaystyle h = \frac{a}{2·tan(π/2/7)} \)

Perimeter \(P\)

\(\displaystyle P = 7·a \)

Area \(A\)

\(\displaystyle A = \frac{7}{4} · a^2 · tan\left(\frac{450°}{7}\right)≈3.63391·a^2 \)

Outer circle radius \(ro\)

\(\displaystyle ro = \frac{a}{2·sin(π/7)} \)

Inner circle radius \(ri\)

\(\displaystyle ro = \frac{a}{2·tan(π/7)} \)

Angle

\(\displaystyle α = \frac{5}{7}·180°≈128.57° \)

Heptagon calculator

Calculate heptagons online