Spike's Calculators

Calculate the area and perimeter of a octagon.

This calculator uses metres for measurements.

Octagon = a shape with eight equal-length sides.

- side length in metres
- decimal precision, the number of digits after the decimal point

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

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

one metre (m) = 3.28083989501312 feet (ft) one metre (m) = 39.3700787401575 inches (in) one square metre (m²) = 10.7639104167097 square feet (ft²) one square metre (m²) = 1550.0031000062 square inches (in²)