Area Calculator FAQ
How do you find the area of a regular polygon?
You need the number of sides and one matching measure. This calculator supports side length, perimeter and apothem, apothem, circumradius, and the classic side-and-apothem formula for regular polygons.
What is the formula for the area of a regular polygon with side length?
A common formula is A = n a^2 / (4 tan(pi/n)), where n is the number of sides and a is the side length.
How do you find the area of a regular polygon from the apothem?
If you know the number of sides and the apothem r, you can use A = n r^2 tan(pi/n). Another equivalent form is A = P r / 2 if the perimeter is known.
How do you find the area of a regular polygon from the perimeter and apothem?
Use A = P r / 2, where P is the perimeter and r is the apothem.
What is the classic regular polygon area formula?
The classic formula is A = n × a × r / 2, where n is the number of sides, a is the side length, and r is the apothem.
How do you find the area of a regular polygon from the circumradius?
Use A = n R^2 sin(2pi/n) / 2, where R is the circumradius and n is the number of sides.
Can this calculator be used for a regular pentagon or hexagon?
Yes. Enter 5 sides for a regular pentagon, 6 sides for a regular hexagon, 8 sides for a regular octagon, and so on.
Does the number of sides have to be an integer?
Yes. A regular polygon must have a whole number of sides, and it must be at least 3.
