Pentagon Calculator

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m
Area
43.0119m²

Total enclosed surface of the pentagon.

Perimeter25m
Side length (a)5m
Diagonal (d)8.0902m
Height (h)7.6942m
Apothem / inradius (r)3.441m
Circumradius (R)4.2533m

Side 5 m: area 43.0119 m squared, perimeter 25 m.

  • Area scales with the square of the side: doubling the side quadruples the area.
  • The diagonal equals 1.618 times the side, the golden ratio built into the shape.
  • The height (7.6942 m) spans the widest pair of parallel sides and is useful for tiling or fitting into a rectangle.
  • Each interior angle is exactly 108 degrees; the five angles always sum to 540 degrees.

Next stepUse the circumradius to fit the pentagon inside a circle, or the apothem to find the radius of the largest inscribed circle.

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