Regular Polygon Calculator
Calculate area and perimeter of a regular polygon.
How to Use the Regular Polygon Calculator
Enter the number of sides and side length to calculate perimeter and area for a regular polygon.
Practical Example
A regular octagon with side length 5 has perimeter 40 units; the calculator also estimates its area from the standard regular-polygon formula.
Factors That Affect the Result
The shape must be regular, meaning all sides and interior angles are equal. Irregular polygons need more detailed measurements.
Frequently Asked Questions
What is a regular polygon?
A polygon with equal sides and equal interior angles.
Can I calculate a triangle?
Yes, if it is equilateral.
What units are returned?
Perimeter uses linear units and area uses squared units.
Related Tools
Working with Regular Polygons
A regular polygon has equal side lengths and equal interior angles. Perimeter is the number of sides multiplied by side length, while area can be found from perimeter and apothem or from a side-length formula.
Confirm that the shape is actually regular before using these formulas. For practical layouts, small measurement errors can accumulate across many sides, so verify side length and apothem carefully. Borders, kerf and construction tolerances should be handled separately from the ideal geometric area.