A driveway commonly features a gravel rock, asphalt or concrete surface. Cost is often times a factor when choosing a material to use on a driveway. Determining cost first begins with proper measurement. Once the basic driveway design, including width and length, is established, measurements can be taken to determine the square footage of the driveway. These measurements can then be converted into square yards, which is a common reference for driveway materials.

Measure the length of the driveway with a tape measure and note the measurement on a note pad with a pencil.

Measure the width of the driveway with the tape measure. Note the measurement on the note pad.

Measure offsets such as circles and triangular-shaped areas. Note the circumference of circles and base and height of triangular-shaped areas.

Calculate the measurements. Multiply the length of the driveway by the width for the overall square footage.

Calculate the area of a triangle by using the formula 0.5(base X height). Multiply the base measurement of the triangle by the triangle height measurement for a total. Multiply the total by 0.5 or 1/2.

Use the formula pi(radius x radius) for a circular area. Multiply the radius (1/2 of the circumference) by itself and note the total. Multiply the total by pi or 3.1416 to determine the circular area.

Add all of the square foot area totals together for a grand total. Divide the grand total by 9 (1 square yard = 9 square feet) to determine the square yardage of the driveway.