Regular Polygon Calculator
Solve a regular polygon from number of sides plus side length, inradius, circumradius, or area, including perimeter, area, angles, apothem, and diagonals.
Regular polygon solver
The broader English intent for regular polygon calculator is not just area. Users expect one known length plus the number of sides to determine side length, perimeter, area, apothem or inradius, circumradius, interior angle, exterior or central angle, and useful diagonals.
P is perimeter, n is number of sides, and s is side length.
r is inradius or apothem.
R is circumradius, the distance from center to vertex.
What the result includes
- Area and perimeter.
- Side length, inradius or apothem, and circumradius.
- Interior angle, central angle, and sum of interior angles.
- Longest diagonal for a quick size check.
Frequently Asked Questions
Sources and References
- Regular Polygon CalculatorCalculatorSoup
- Regular Polygon CalculatorCalcTool
- Polygon CalculatorGraphCalc
- Regular PolygonWolfram MathWorld
Calculations are based on the listed reference sources. Links open in a new tab.
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