Pentagon Area Calculator

Calculate the area and perimeter of a regular pentagon.

Input Dimensions

Side length (s)

Pentagon Dimensions

Area (A)172.0477

Perimeter (P)50.0000

Apothem (a)6.8819

Circumradius (R)8.5065

About this calculator

What is a Regular Pentagon?

A regular pentagon is a five-sided polygon with all sides and interior angles equal. Each interior angle of a regular pentagon is 108 degrees.

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Pro Tips

Fun Facts

"The Pentagon in Washington D.C. is one of the world's largest office buildings and is famous for its shape."
"Pentagonal symmetry is rare in inanimate minerals but common in living organisms like starfish."

Formula: Area = (1/4) * √(5(5 + 2√5)) * s²