Perimeter

Perimeter[reg] gives the perimeter of the two-dimensional region reg.

Perimeter[{x1,x2},{s,smin,smax},{t,tmin,tmax}] gives the perimeter of the parametrized region whose Cartesian coordinates xi are functions of s and t.

Perimeter[{x1,x2},{s,smin,smax},{t,tmin,tmax},chart] interprets the xi as coordinates in the specified coordinate chart.

Examples

Compute the perimeter of a disk:

Perimeter[Disk[]]
(* 2 Pi *)

Compute the perimeter of a rectangle:

Perimeter[Rectangle[{0, 0}, {3, 4}]]
(* 14 *)

Please visit the official Wolfram Language Reference for more details.