Convert Acre (US Survey) (ac (US)) to Section (section) instantly.
About these units
Acre (US Survey) (ac (US))
The US survey acre is based on the US survey foot, making it slightly different from the international acre. With a value of 43,560 survey-square feet, it appears extensively in historical property records and federal land surveys. Because millions of acres in the United States were mapped using PLSS, the survey acre remains necessary for interpreting legal land rights, even though modern mapping often uses metric units or the international foot. This specialized acre illustrates how subtle unit differences can survive for centuries due to legal and administrative inertia.
Section (section)
A section is a unit of area equal to one square mile, or 640 acres, derived from the PLSS township system. Each township contains 36 sections arranged in a 6-by-6 grid. Sections were historically granted to settlers, railroads, and states for development, education funding, and agricultural expansion. Because a section is large but manageable, it provided a logical unit for dividing land among homesteaders. Even today, the section persists as a foundation of rural property boundaries. Many farms, ranches, and municipal boundaries reference section lines, reflecting how 19th-century surveying still shapes 21st-century land use.