Area of a Regular Polygon Calculator
A = ¼ × n × s² × cot(π/n) for an n-gon with side length s.
Result
General calculation reads
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How to use this calculator
- Enter the number of sides (3 or more).
- Enter the side length.
- Read area, apothem, circum-radius, and perimeter.
About this calculator
A regular polygon has equal-length sides and equal interior angles. The classic formula A = ¼ n s² cot(π/n) collapses to familiar special cases — equilateral triangle (n=3): √3/4 s²; square (n=4): s²; regular hexagon (n=6): 3√3/2 s². The "apothem" is the distance from center to side midpoint.
Frequently asked
What is the apothem?+
When does the regular-polygon formula become a circle?+
What's the interior angle?+
How does this differ from area-triangle for n=3?+
Can I use this for irregular polygons?+
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