Regular Polygon Calculator

Enter number of sides.
Enter side length.
Math

Calculate regular polygon with explicit inputs and a worked example.

Formula

A = ns²/[4 tan(π/n)]; P = ns

Example Calculation

Example inputs
  • Number of sides: 6
  • Side length: 2

A regular hexagon of side 2 has perimeter 12 and area about 10.3923.

Frequently asked questions

How do I use this calculator?

Enter number of sides, side length. The result updates automatically. Use Reset to restore the example values.

What method does it use?

A = ns²/[4 tan(π/n)]; P = ns. Follow the units and definitions shown with the inputs to apply this relationship consistently.

Why might a rounded result differ?

The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.

Are my inputs saved online?

No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.

Check the assumptions and units before using this result. Read about calculation methods.