PLSS Section Area Calculator
The PLSS section area calculator converts Public Land Survey System legal descriptions into acreage. Select the subdivision type (township, section, quarter section, or quarter-quarter section) and enter the number of such units to find the total area. The PLSS is used throughout the US west of the original 13 colonies to describe real property, agricultural land, and public lands managed by the BLM and USFS. This tool is useful for real estate, agricultural planning, and land-use analysis.
PLSS area hierarchy
Township = 36 sections = 23,040 acres (6 mi x 6 mi)
Section = 640 acres (1 mi x 1 mi)
Quarter section = 160 acres (1/2 mi x 1/2 mi)
Quarter-quarter section = 40 acres (1/4 mi x 1/4 mi)
These are nominal areas. Actual recorded acreages may differ slightly due to survey closure errors, particularly in fractional sections along township boundaries.
Reading PLSS legal descriptions
- A full legal description reads from smallest to largest: "NW 1/4 of the SE 1/4 of Section 15, Township 2 North, Range 5 East, 6th Principal Meridian."
- Township numbering increases north (T1N, T2N) or south (T1S) from the baseline.
- Range numbering increases east (R1E, R2E) or west (R1W) from the principal meridian.
- The BLM General Land Office Records portal provides original survey plats at glorecords.blm.gov.
PLSS section area calculator: frequently asked questions
What is the Public Land Survey System (PLSS)?
The PLSS is the US federal land survey system used to describe land ownership west of the original 13 colonies. It divides land into townships (6 miles square), sections (1 mile square = 640 acres), and further subdivisions down to quarter-quarter sections (40 acres).
How many acres is a section?
A section is 1 square mile, equal to 640 acres. It is the basic unit of the PLSS. Sections are numbered 1 to 36 within each township, starting in the northeast corner and snaking westward then eastward in alternating rows.
How many acres is a quarter section?
A quarter section is one-fourth of a section: 160 acres. It is described as the NE, NW, SE, or SW quarter. Homestead Act claims in the 1800s were typically one quarter section (160 acres).
What is a quarter-quarter section?
A quarter-quarter section is one-fourth of a quarter section, equal to 40 acres. It is the smallest regularly subdivided PLSS unit and is described as, for example, the NW 1/4 of the SE 1/4 of Section 15. Field size of 40 acres is common in agricultural descriptions.
Are PLSS sections always exactly 640 acres?
Nominal sections are 640 acres, but in practice sections along the north and west boundaries of a township are often irregular (fractional sections) because they absorb the accumulated errors from survey closure. These are described as Lots 1, 2, 3, etc. and are recorded in the PLSS records.
Official sources
- BLM General Land Office Records: BLM GLO survey plats and records.
- USGS: USGS PLSS and land survey references.
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.