where s in the above formula is given by s = (1 / 2)(a + b + c).
__How to use the calculator__

Enter the three sides a, b and c, of the triangle, as positive real numbers and press "enter". The output is the area and the triangle. For the three sides a, b and c to define a triangle, the sum of the lengths of any two sides must be larger than the length of the third side. Note that if the three sides do not define a triangle 'No Triangle Exists' is displayed.

More Online Geometry Calculators and Solvers.