How To Measure Square Feet For Granite Countertops. Measure the length of your countertop along the wall in inches. A square foot is 12” x 12” = 144.
Divide the total sq, inches of 3660 by 144 to get the square footage of your counter tops. To calculate the area of each countertop section, multiply the length times the width. 3,744 plus 576 equals 4,320 square inches.
Area = length × width
Measure the height of any backsplashes. A square foot is 12” x 12” = 144. Area = length × width Do not include areas where the countertop will not cover, such as oven ranges, in your boxes.