Octagon Calculator
MathCalculate the perimeter, area, and radii of a regular octagon from its side length.
Area
Area of the regular octagon.
Perimeter
40.0000
Total perimeter.
Circumcircle Radius
6.5328
Radius of the circle passing through all vertices.
Incircle Radius (Apothem)
6.0355
Radius of the inscribed circle touching all sides.
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Odeh Ahwal0people find this calculator helpful
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Calculator Stats
Creators
Odeh Ahwal0people find this calculator helpful
Views
Helpful
Saved
Embeds
Frequently Asked Questions
How is octagon area calculated?
A regular octagon's area equals 2 times 1 plus the square root of 2, times the side length squared, approximately 4.828 times side squared.
Where is the classic stop-sign octagon shape used?
The regular octagon is best known as the shape of stop signs in many countries, chosen for its distinctive shape that remains recognizable even when partly obscured, unlike a circle or square.
What is the interior angle of a regular octagon?
Each interior angle is 135 degrees, found from (n minus 2) times 180 divided by n, with n equal to 8.
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