Perimeter of an Octagon Calculator

Summary

A regular octagon is an eight-sided polygon where all sides are equal in length and all interior angles are equal. Its perimeter is simply eight times the side length, expressed as P = 8s. This calculator lets you enter a side length in your preferred unit and instantly returns the perimeter.

How it works

1. Enter the side length of the regular octagon.
2. Select the unit of measurement (mm, cm, m, in, ft, yd).
3. The calculator applies the formula P = 8s in real time.
4. The result is displayed in the same unit you selected.
5. Click "Copy Result" to copy the perimeter value to your clipboard.

Use cases

• Find the total border length needed to frame an octagonal mirror or window.
• Calculate fencing or trim material for an octagonal gazebo or deck.
• Solve geometry homework problems involving regular octagons.
• Verify hand calculations for construction or woodworking projects.
• Convert octagon dimensions across different units of measurement.
• Quickly check perimeter for tiled octagonal floor layouts.

Frequently Asked Questions