PLSS legal description reader
Reads a Public Land Survey System description like NE¼ SW¼ Sec 12, T3N R4W, 6th PM into plain words, and gives the nominal aliquot area of a standard 640-acre section.
Experimental: not yet fully verified. How results are checked
This is the northeast quarter of the southwest quarter of section 12, township 3 north, range 4 west, Sixth Principal Meridian. Nominal area: 40 US survey ac.
- The area assumes a standard 640-acre section. Real sections vary, and lots are not nominal.
- Nominal area
- Section
- Township
- Range
- Principal meridian
- Meridian code
Provenance
- Computed by
- survey.land.plss-parse 1.0.0, core 0.1.0
- Model
- Aliquot parts in words (NE¼ SW¼ is the northeast quarter of the southwest quarter); nominal area = 640 acres × the product of the fractions
- Accuracy
- Nominal only: real sections vary from 640 acres, and fractional sections and lots are not nominal. Locating the parcel needs the BLM section geometry.
- Notes
- 2 shown with the answer
- Cites
- Bureau of Land Management, Manual of Surveying Instructions for the Survey of the Public Lands of the United States
Something look off?
How we got thisFormula, worked example, sources, and proof
Model: Aliquot parts in words (NE¼ SW¼ is the northeast quarter of the southwest quarter); nominal area = 640 acres × the product of the fractions
Accuracy: Nominal only: real sections vary from 640 acres, and fractional sections and lots are not nominal. Locating the parcel needs the BLM section geometry.
Worked example: NE¼ SW¼ Sec 12, T3N R4W, 6th PM. Source: add-practitioner-essentials PLSS scenario: the northeast quarter of the southwest quarter of section 12, nominal 40 acres. It is golden test vector v001, and every build checks the tool still gives its answer within its tolerance.
You enter
- Description
- NE¼ SW¼ Sec 12, T3N R4W, 6th PM
You get
- In words
- the northeast quarter of the southwest quarter of section 12, township 3 north, range 4 west, Sixth Principal Meridian
- Nominal area
- 40 US survey ac
- Section
- 12
- Township
- 3N
- Range
- 4W
- Principal meridian
- Sixth Principal Meridian
- Meridian code
- 06
- Location
- To locate it, install the state's BLM PLSS data (CadNSDI); aliquot lines are never drawn by quartering an ideal square.
- Notice
- Parsing and arithmetic aid. Boundary determination requires a licensed surveyor and the governing records.
Review: Not yet independently reviewed by a licensed surveyor.
Last verified: 2026-09-18, when a maintainer last confirmed this tool's sources at the issuer. See the sources ledger.
Status: version 1.0.0, core 0.1.0. See this tool in the verification report.
Checked against: 5 golden test vectors (download the test vectors, each with its source and tolerance). See how results are checked and every source.
Sources
- Manual of Surveying Instructions for the Survey of the Public Lands of the United States, Bureau of Land Management, 2009 Manual. Chapter 1 (units: chain of 66 feet, link of 0.66 feet) and Chapter 3 (subdivision of sections, aliquot parts).
Terms
- PLSS: Public Land Survey System
- The US rectangular survey of townships, ranges, and sections, carried out by the federal government since 1785. Source: Manual of Surveying Instructions (BLM)
Experimental means this tool has not yet met the stable bar: at least 20 golden vectors, differential tests, and an independent worked example.