Polygon Calculator

Calculate regular polygon area, perimeter, apothem, and circumradius. Given sides and radius or side length, get all properties instantly.

Must be 3 or more

Regular Polygon Formulas

Area (using side)

A = (n × s²) / (4 × tan(pi/n))

Area (using apothem)

A = (1/2) × P × a

where P = perimeter, a = apothem

Perimeter

P = n × s

Interior Angle

Angle = ((n - 2) × 180) / n

Frequently Asked Questions

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