Triangle Calculator

Calculate sides, angles, and area of any triangle.

Triangle Geometry Basics

A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry.

Common Formulas

  • Perimeter: a + b + c
  • Area (Heron's Formula): √[s(s-a)(s-b)(s-c)], where s is the semi-perimeter.
  • Triangle Inequality: The sum of any two sides must be greater than the third side.