This **square footage calculator** finds the square footage of a house, room, property, lot or land with any of the following shape rectangle, triangle, trapezoid, square, circle or rhombus.

## Square footage formulas

The algorithm behind this *square footage calculator* uses the following formulas depending on the shape:

**Triangle**SF can be obtained if the 3 sides of the it are known:

SF triangle = Square root(S * (S - Edge 1) * (S - Edge 2) * (S - Edge 3))

Where S = (Edge 1 + Edge 2 + Edge 3) / 2

**Rectangle**requires the width and the length of the rectangle to be given:

SF rectangle = Length * Width

**Square**requires that its side to be provided:

SF square= Side * Side

**Trapezoid**calculation requires that the top edge, bottom edge, left side and right side to be known:

SF trapezoid = Height * (top edge + bottom edge) / 2

Where:

Height = (Square root(s * (s - l1) * (s - l2) * (s - l3))) / l3

l1 = left side

l2 = right side

l3 = bottom edge – top edge

s = (l1 + l2 + l3) / 2

**Circle**SF can be estimated in case the circle radius is known:

SF circle = π * Radius * Radius

Where: π = 3.14159265359

**Rhombus**requires that the base and its height to be given:

SF rhombus = Base * Height

Where:

SF = square footage

16 Apr, 2015