Area of Regular Pentagon Calculator

Enter the side length to calculate the area instantly.

Side Length

About Area of Regular Pentagon

The Area of Regular Pentagon Calculator is a free and accurate tool that helps you calculate the area of a regular pentagon using just the side length. Whether you're solving geometry problems, working on design projects, or handling construction tasks, this calculator gives you quick and precise results every time.

What Is a Regular Pentagon?

A regular pentagon is a five-sided polygon where all sides and interior angles are equal. It appears in geometry, architecture, and art. Calculating the area manually can be tedious, but this tool simplifies it in seconds.

Formula for Area of a Regular Pentagon:

Using trigonometry (cotangent form):

Area = (5 / 4) × a² × cot(π / 5)

Where a is the side length and cot(π/5) ≈ 1.37638.

Algebraic closed form:

Area = (1 / 4) × √5 × (5 + 2√5) × a²

Example Calculation:

If the side length a = 6 cm, then:

Area = (1/4) × √5 × (5 + 2√5) × 6² ≈ 61.94 cm²

✅ So, the area of the regular pentagon is approximately 61.94 square centimeters.

Features of the Calculator:

Simple Input – Enter just the side length.

All Units – Works with cm, m, in, ft, and more.

Instant Results – Accurate output in one click.

No Sign-Up – 100% free, no installation required.

Common Use Cases

Education – Geometry & trigonometry problems.

Architecture & 3D – Modeling and design workflows.

Planning – Tile layouts and decorative patterns.

Projects – Demos, competitions, and classroom use.

Quickly and accurately find the area of any regular pentagon — your trusted solution for geometry made simple!