CalculatorCast
Math Finance Health & Fitness Date & Time Unit Converters Computer Physics Chemistry Construction Engineering Statistics Education Everyday Life Biology Automotive Cooking & Food Sports & Fitness Real Estate Photography Electrical Agriculture Travel Business
All Calculators Favorites ()
English Español Français Deutsch Português Italiano Nederlands Polski Türkçe 日本語 한국어 Svenska Norsk Dansk Suomi עברית

Polygon Calculator

Compute interior angle sums and area of a regular polygon.

Introduction

Polygon Calculator — Compute interior angle sums and area of a regular polygon. Enter Number of sides, Side length (optional) to get an instant, accurate result.

Formula

Sum of interior angles = (n−2)×180°. Each interior angle (regular polygon) = sum/n. Area of a regular polygon with side length s = (n×s²) / (4×tan(π/n)).

Step-by-step

  1. Enter the Number of sides.
  2. Enter the Side length (optional).
  3. Click Calculate to see your result instantly.

Real-world example

Example: With Number of sides = 6, Side length (optional) = 4, the Polygon Calculator gives Interior Angle Sum: 720, Each Interior Angle: 120, Area: 41.5692.

Frequently Asked Questions

Does the interior angle sum depend on side length?
No, the sum of interior angles depends only on the number of sides, n.
Is the area formula valid for any polygon?
It assumes a regular polygon, where all sides and angles are equal.
What inputs does the Polygon Calculator need?
You'll need to provide: Number of sides, Side length (optional). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.
How accurate is the Polygon Calculator?
The Polygon Calculator applies the formula exactly as calculated — Sum of interior angles = (n−2)×180°. Each interior angle (regular polygon) = sum/n. Area of a regular polygon with side length s = (n×s²) / (4×tan(π/n)). — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.
Is the Polygon Calculator free to use?
Yes, the Polygon Calculator is completely free, requires no signup, and runs instantly in your browser.

About the Polygon Calculator

The Polygon Calculator uses a real, verifiable formula — Sum of interior angles = (n−2)×180°. Each interior angle (regular polygon) = sum/n. Area of a regular polygon with side length s = (n×s²) / (4×tan(π/n)). — so results are accurate every time, not an approximation.