For builders, architects and engineers, length and width conversion is critical to doing a good job. A mistake in one of these fields can lead to serious injury. Students must have a firm understanding of them as well. In particular, they should learn how to convert square inches to cubic feet.

Examine the input measurements you have and the question that is being posed. For example, suppose you have the square inch dimensions for the base of a box as well as its height and are trying to determine the volume in cubic feet.

Calculate the cubic-inch volume by multiplying the base's square-inch area and height provided. For example, if your box's base equals 300 square inches and the box is 18 inches high, you would multiply these figures together to get 5,400 cubic inches.

Use the knowledge that 1,728 cubic inches equals one cubic foot. This is derived from this computation:

12 inches * 12 inches * 12 inches = 1,728 cubic inches, or 1 cubic foot

Each 12-inch unit represents a foot in length, width and height.

Divide the cubic inches number in Step 2 by the conversion for a cubic foot in Step 3:

5,400 / 1,728 = 3.125 cubic feet.