The semi-perimeter of a triangle calculator Triangle computes half the length of the perimeter of a triangle.
INSTRUCTIONS: Choose units and enter the following:
Semi-Perimeter (s): The calculator computes the semi-perimeter in meters. However, this can be automatically converted to many other length units (e.g. inches) via the pull-down menu.
This formula also confirms that the three length can form a triangle. If not, an error message is returned.
The formula for the semi-perimeter of a triangle is:
s = (a + b + c) / 2