Spike's Calculators

Calculate the area and perimeter of a octagon. This calculator uses feet and or inches for measurements.

Octagon = a shape with eight equal length sides.

- side length in feet and or inches
- decimal precision, the number of digits after the decimal point

- length of the long diagonal (ld) in decimal feet
- side to side length (ss) in decimal feet
- length of the short diagonal (sd) in decimal feet
- the area of the octagon in decimal square feet
- area in square feet and inches
- the area in decimal square inches
- the area in square inches
- the area in square metres
- the perimeter of the octagon in decimal feet
- the perimeter in lineal feet and inches
- the perimeter in decimal inches
- the perimeter in inches
- the perimeter in metres

A = 4.8284271a² P = a8 where A is the area of the octagon a the length of a side P the perimeter of the octagon

one square foot ( ft²) = 144 square inches (in²) one square inch (in²) = 0.00694444444444443 square feet (ft²) one square foot ( ft²) = 0.09290304 square metres (m²) square inch (in²) = 0.00064516 square metres (m²)