Convert Acre to Square Meter
Convert acres to square meters instantly. 1 acre = 4046.8564224 square meter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Meter to Acre converter for the reverse conversion.
Units explained
Acre
An acre is an imperial unit of area equal to exactly 4046.8564224 m². It is the most widely used non-metric unit for land area, particularly in the US, UK, and India.
Originally defined in medieval England as the area one yoke of oxen could plow in a day, approximately 40 perches by 4 perches. Standardized via the 1959 International Yard and Pound Agreement.
Acres are the standard land measurement unit in the US (real estate, agriculture), the UK (rural property), and widely used in India (alongside hectares and traditional regional units). 1 acre = 4840 sq yd = 43,560 sq ft = 0.4047 hectare.
Medieval English farming origin; modern exact value standardized in 1959.
Square Meter
A square meter is the SI base unit of area, defined as the area of a square with sides of one meter. It is the universal scientific unit for area.
Defined by squaring the meter, which was redefined in 2019 in terms of the speed of light. The meter itself was originally proposed by the French Academy of Sciences in 1791 as 1/10,000,000 of the distance from the equator to the North Pole.
Square meters are the universal SI unit for area, used in real estate (most countries outside the US/UK), construction, physics, engineering, materials science, biology, and nearly all scientific contexts worldwide.
Meter adopted as SI base unit in 1960; current exact definition via speed of light dates to 2019.
Acre to Square Meter conversion formula
The relationship between acres and square meters:
To convert acres to square meters, multiply the value in acres by 4046.8564224. To reverse, multiply square meters by 0.0002471054.
How to use this converter
Type a value into the calculator. The result in square meters updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Square Meter to Acre converter for the reverse direction.
Step-by-step: convert acres to square meters
- Write down the value in acres (ac).
- Multiply that value by the factor 4046.8564224.
- The product is the equivalent value in square meters (m²).
- To reverse, multiply the square meter value by 0.0002471054.
Worked examples
Example 1 — Convert 1 ac to m²:
1 × 4046.8564224 = 4046.8564224 m²
Example 2 — Convert 100 ac to m²:
100 × 4046.8564224 = 404685.64224 m²
Real-world example — Lap pacing and route segmentation
Translating a acre-scale distance into square meters is how runners, cyclists, and route planners convert top-line totals into the working segments they actually pace and execute.
1 ac × 4046.8564224 = 4046.8564224 m²
Real-world example — Track athletics distances
A 1-acre running track equals one thousand square meters. Track athletes' lap pacing converts the lap (often 400 of the smaller unit) into the fractional race distance whenever a coach reviews splits.
1 ac × 4046.8564224 = 4046.8564224 m²
Real-world example — Geographic to human-scale conversion
One acre converts to a precise number of square meters — the everyday arithmetic for navigation systems, race-distance calculations, and any context where bigger geographic units must be related to the smaller working units.
1 ac × 4046.8564224 = 4046.8564224 m²
Acre to Square Meter conversion table
Standard reference values for converting acres to square meters:
| Acre [ac] | Square Meter [m²] |
|---|---|
| 0.01 | 40.468564224 |
| 0.1 | 404.68564224 |
| 1 | 4046.8564224 |
| 2 | 8093.7128448 |
| 3 | 12140.5692672 |
| 4 | 16187.4256896 |
| 5 | 20234.282112 |
| 10 | 40468.564224 |
| 20 | 80937.128448 |
| 30 | 121405.692672 |
| 40 | 161874.256896 |
| 50 | 202342.82112 |
| 100 | 404685.64224 |
| 500 | 2023428.2112 |
| 1000 | 4046856.4224 |
Frequently asked questions
How many square meters is 1 acre?
How do I convert acres to square meters?
How do I convert square meters back to acres?
How many square meters is 100 acres?
Popular area unit conversions
Convert Acre to other area units
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Metric / SI (16 units)
Imperial / US Customary (14 units)
US Survey (5 units)
Indian Subcontinent (16 units)
Other Regional (10 units)
Scientific / Physics (5 units)
Historical / Pre-metric European (6 units)
Sources & references
Conversion factor (1 ac = 4046.8564224 m²) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.