Fidamen

Convert Square Meters to Acres - Area Converter

This converter converts area in square meters (m²) to acres (ac) using the standardized international relationship between SI area units and traditional land-area units.

The conversion factor is fixed by international measurement conventions and is suitable for engineering calculations, GIS workflows, planning estimates, and general use. For legal land surveys or property deeds, consult your licensed surveyor or local cadastral authority as regulations and rounding rules may differ.

Results are presented with full-precision internally; display rounding is configurable in many tools — consider required tolerance before reporting (see FAQs for guidance on precision and regulatory considerations).

Updated Nov 21, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record e2a85f4e7bd2 • Reviewed by Fidamen Standards Committee

Interactive Converter

Convert between square meter and acre with precision rounding.

Quick reference table

Square MeterAcre
1 m²0.0002 ac
5 m²0.0012 ac
10 m²0.0025 ac
25 m²0.0062 ac
50 m²0.0124 ac
100 m²0.0247 ac

Methodology

We use the exact internationally accepted equivalence between acres and square meters. The canonical value used here is: 1 acre = 4,046.8564224 square meters.

To convert, the calculator divides the input in square meters by 4,046.8564224 to produce acres. This factor is consistent with national metrology and international standards (see citations).

Worked examples

1000 m² → acres = 1000 ÷ 4,046.8564224 ≈ 0.247105381 acres

5,000 m² → acres = 5000 ÷ 4,046.8564224 ≈ 1.235526905 acres

4046.8564224 m² → acres = 4046.8564224 ÷ 4,046.8564224 = 1 acre

F.A.Q.

What exact conversion factor do you use?

We use the internationally accepted value 1 acre = 4,046.8564224 square meters, which is consistent with national metrology institutes and international SI guidance.

How many decimal places should I report?

That depends on use: for high-precision engineering or GIS workflows keep at least six decimal places for acres; for general land area summaries two to three decimal places is common. For legal documents follow the rules of the local land registry or a licensed surveyor.

Is this conversion suitable for legal surveys or property titles?

This tool provides mathematical conversions only. Legal surveys require certified measurements and may use jurisdictional rounding, tie-breaker rules, or preferred units. Consult a licensed surveyor or your local cadastral authority for legally binding figures.

How do I convert back from acres to square meters?

Multiply acres by 4,046.8564224. Example: 2 acres × 4,046.8564224 = 8,093.7128448 m².

I have measurements with instrument uncertainty. How should I treat uncertainties when converting?

Convert the central value with the same factor and propagate uncertainty by dividing the absolute uncertainty in m² by 4,046.8564224 to get the uncertainty in acres. For percentage or relative uncertainties, the relative uncertainty remains the same under this linear conversion.

Can I convert large lists or CSV files of areas?

Yes. For batch conversions export your values as numeric square-meter fields and apply the same division by 4,046.8564224 programmatically (spreadsheet formula: =A2/4046.8564224). Ensure numeric formatting preserves required precision.

Are there regional variants of the acre?

The international acre used here is the standard (international acre). Historical or regional acres (for example, some traditional local units) can differ; confirm unit definitions before converting historical data.

Where does this factor come from and who publishes it?

The factor is published and maintained by national metrology institutes and international standards organizations. See the cited references (NIST, BIPM) for official guidance and SI relationships.

Sources & citations

Further resources

Versioning & Change Control

Audit record (versions, QA runs, reviewer sign-off, and evidence).

Record ID: e2a85f4e7bd2

What changed (latest)

v1.0.0 • 2025-11-21 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Public QA status

PASS — golden 25 + edge 120

Last run: 2026-01-23 • Run: golden-edge-2026-01-23

Engine

v1.0.0

Data

Baseline (no external datasets)

Content

v1.0.0

UI

v1.0.0

Governance

Last updated: Nov 21, 2025

Reviewed by: Fidamen Standards Committee (Review board)

Credentials: Internal QA

Risk level: low

Reviewer profile (entity)

Fidamen Standards Committee

Review board

Internal QA

Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person

Semantic versioning

  • MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
  • MINOR: New features or fields that do not change existing outputs for the same inputs.
  • PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.

Review protocol

  • Verify formulas and unit definitions against primary standards or datasets.
  • Run golden-case regression suite and edge-case suite.
  • Record reviewer sign-off with credentials and scope.
  • Document assumptions, limitations, and jurisdiction applicability.

Assumptions & limitations

  • Uses exact unit definitions from the Fidamen conversion library.
  • Internal calculations use double precision; display rounding follows the unit's configured decimal places.
  • Not a substitute for calibrated instruments in regulated contexts.
  • Jurisdiction-specific rules may require official guidance.

Change log

v1.0.0 • 2025-11-21 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 33d10ba84d5a