Most commonly associated with the shape of a "Stop" sign, the octagon has eight sides that are equal in length. The circumference of an octagon, also known as the perimeter, can be calculated by using a simple mathematical formula and a length measuring device such as a tape measure.

- Tape measure
- Calculator

Measure one side of the octagon using a tape measure. Because each side of the octagon should measure the same length, taking the measurement of one side should suffice for finding the circumference.

Multiply the length you measured by 8 or simply add up all eight sides. The answer should be the same and give you the circumference of the octagon shape. For example, if one of the sides of the octagon measures 3 inches, the circumference of the octagon would be 24 inches -- 3 x 8 = 24 or 3 + 3 + 3 + 3 + 3 + 3 +3 + 3 = 24.

Convert the unit value of the circumference to another length measurement unit, such as feet and meters. You can use an online length conversion tool or complete the conversion mathematically. For example, if the circumference of your octagon was 24 inches, it would equal 2 feet because there are 12 inches in each foot.

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About the Author

Paul Lin has been writing professionally since 2010. He has written scripts for the National Science Foundation and short films that have won awards at film festivals. Lin holds a Bachelor of Arts in scriptwriting from the University of North Texas.

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