Mathematics · Geometry

Regular Polygon Calculator

Calculate regular polygon area and perimeter from side count and side length.

Runs locally
Your numbers

Inputs and results stay in this browser. Change one value at a time to explore the relationship.

Your inputCalculatedPassed forward in chains
Area2.598076
Perimeter6
Apothem0.866025

Calculation steps

  1. Area=6×1²÷(4tan(π/6))=2.598076211353316.

Problem → model → reason → result

What problem does this model solve?

Calculate regular polygon area and perimeter from side count and side length.

Why does the model apply?

The center divides a regular polygon into congruent isosceles triangles.

What assumptions does it make?

Lengths use one consistent unit, the named shape is ideal, and dimensions refer to the perpendicular or straight-line measurements specified by the model.

Formula

A=ns²/[4tan(π/n)]

Calculation and working

The calculator above substitutes your inputs into the model and leaves the calculation steps visible so the answer can be checked rather than merely accepted.

What does the result mean?

The result answers the stated problem in the units implied by your inputs. Read its sign, size and units together, then compare it with the original values before drawing a conclusion.

Worked example

A unit regular hexagon has area about 2.598.

Common mistake

n must be at least three and all sides and angles must be equal.

When does this model not apply?

Irregular shapes, measurement error and non-ideal surfaces require a more detailed model or measured uncertainty.

How to learn with this calculator

Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.

Clear answers

Frequently asked questions

What does the Regular polygon do?

Calculate regular polygon area and perimeter from side count and side length.

How does the Regular polygon work?

The calculator applies A=ns²/[4tan(π/n)]. The center divides a regular polygon into congruent isosceles triangles.

What can I learn from the Regular polygon?

It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.

Last reviewed 2026-07-14. Calculations tested 2026-07-14.