Square feet to acres
Converts ft2 to ac using exact unit definitions.
43,560 ft² is 1 ac.
- Input
Provenance
- Computed by
- units.area.ft2-to-ac 1.0.0, core 0.1.0
- Model
- Exact unit definitions
- Accuracy
- Exact to double precision: each conversion is one correctly rounded ratio of exact definitions
- Notes
- None
- Cites
- National Institute of Standards and Technology, Guide for the Use of the International System of Units (SI), NIST Special Publication 811; National Institute of Standards and Technology, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, NIST Handbook 44
Something look off?
How we got thisFormula, worked example, sources, and proof
Model: Exact unit definitions
Accuracy: Exact to double precision: each conversion is one correctly rounded ratio of exact definitions
Worked example: 43560 ft2 in ac. Source: Exact unit definitions (NIST SP 811 Appendix B). It is golden test vector v001, and every build checks the tool still gives its answer within its tolerance.
You enter
- Value
- 43560 ft2
You get
- Converted
- 1 ac
- Input
- 43,560 ft²
Review: Not yet independently reviewed by a metrologist.
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: 3 golden test vectors (download the test vectors, each with its source and tolerance). See how results are checked and every source.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, National Institute of Standards and Technology, 2008 edition. Appendix B.8, Factors for units listed alphabetically.
- Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, NIST Handbook 44, National Institute of Standards and Technology, 2026 edition. Appendix C, General Tables of Units of Measurement.