A surveyor's measure is a set of tools used by surveyors to measure land and other areas. The most common tools are an ACRE, AREA, and ROD. An ACRE is a unit of measurement equal to 4, 840 square yards or 43, 560 square feet. AREA is a measure of the size of a surface, usually measured in square units such as square feet or square meters. A ROD is a unit of length equal to 16.5 feet or 5.5 yards. Together, these three tools are used by surveyors to accurately measure land and other areas.