Convert Acre to Square Foot
Convert acres to square feet instantly. 1 acre = 43560 square foot — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Foot 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 Foot
A square foot is an imperial unit of area equal to exactly 0.09290304 m². It is the dominant unit for real estate area measurement in the United States and is widely used in India for residential property listings.
Derived by squaring the foot. The foot was standardized to exactly 0.3048 m via the 1959 International Yard and Pound Agreement.
Square feet are the standard unit for US real estate floor area, HVAC capacity ratings (BTU per ft²), commercial leasing, and construction. In India, square feet is the dominant unit for residential property advertisements alongside traditional regional units.
Foot dates to ancient civilizations; modern exact value standardized in 1959.
Acre to Square Foot conversion formula
The relationship between acres and square feet:
To convert acres to square feet, multiply the value in acres by 43560. To reverse, multiply square feet by 2.295684e-5.
How to use this converter
Type a value into the calculator. The result in square feet 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 Foot to Acre converter for the reverse direction.
Step-by-step: convert acres to square feet
- Write down the value in acres (ac).
- Multiply that value by the factor 43560.
- The product is the equivalent value in square feet (ft²).
- To reverse, multiply the square foot value by 2.295684e-5.
Worked examples
Example 1 — Convert 1 ac to ft²:
1 × 43560 = 43560 ft²
Example 2 — Convert 100 ac to ft²:
100 × 43560 = 4356000 ft²
Real-world example — Geographic to architectural scale
One acre equals 100,000 square feet. Map scales use this when an architectural site plan (in the smaller unit) must be related to road-network plans (in the larger unit) on the same drawing.
1 ac × 43560 = 43560 ft²
Real-world example — Geographic to architectural conversion
One acre equals 100,000 square feet. The conversion bridges geographic-scale survey work and architectural-scale building plans on the same drawing.
1 ac × 43560 = 43560 ft²
Acre to Square Foot conversion table
Standard reference values for converting acres to square feet:
| Acre [ac] | Square Foot [ft²] |
|---|---|
| 0.01 | 435.6 |
| 0.1 | 4356 |
| 1 | 43560 |
| 2 | 87120 |
| 3 | 130680 |
| 4 | 174240 |
| 5 | 217800 |
| 10 | 435600 |
| 20 | 871200 |
| 30 | 1306800 |
| 40 | 1742400 |
| 50 | 2178000 |
| 100 | 4356000 |
| 500 | 2.178e+7 |
| 1000 | 4.356e+7 |
Frequently asked questions
How many square feet is 1 acre?
How do I convert acres to square feet?
How do I convert square feet back to acres?
How many square feet is 100 acres?
Popular area unit conversions
Convert Acre to other area units
Show all Acre conversions
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 = 43560 ft²) 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 Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.