Square Feet to Acres Converter converts land area from square feet (ft²) to acres (ac), while also showing equivalent values in square meters (m²) and hectares (ha). The calculator is fully bidirectional, meaning you can enter either unit and get all others updated.
About square feet. A square foot (ft²) is the area of a square measuring one foot on each side. Since 1 foot equals 12 inches, one square foot equals 144 square inches. For small or medium-sized properties, ft² provides a convenient level of precision.
About acres. An acre (ac) is a larger unit of land measurement used to describe fields, plots, and real estate parcels. It is defined as exactly 43,560 square feet. In architectural and planning contexts, acres are preferred when dealing with larger sites, where using square feet would yield large and less practical numbers.
About metric equivalents. For coordination with international teams and specification documents, the tool simultaneously displays metric results: square meters (m²) and hectares (ha). The key relationships are 1 ft² = 0.09290304 m², 1 m² ≈ 10.7639 ft², and 1 ha = 10,000 m² ≈ 2.47105 ac.
About workflows. In addition to direct ft² ⇄ ac entry, the tool includes a Length × Width mode. This workflow calculates area from entered dimensions, accepting both imperial (ft+in) and metric (m+cm) combinations. Inputs normalize automatically (e.g., inches ≥ 12 convert to feet), and the system keeps a single internal metric state for maximum precision across all unit systems.
Conversion. Entering square feet multiplies by 0.09290304 to obtain m², which is then expressed in acres by dividing by 4046.8564224. The same logic applies in reverse when acres are entered. For the Length × Width workflow, the calculator multiplies normalized dimensions to find total area and re-renders all equivalent units.
Formulas.
- Area constants (unit relationships):
1 ac = 43,560 ft²; 1 ft² = 0.09290304 m²; 1 ha = 10,000 m². - ft² ⇄ ac (direct conversion):
Aac = Aft² ÷ 43,560 [ft² → ac];
Aft² = Aac × 43,560 [ac → ft²]. - ft² ⇄ m² (exact constant):
Am² = Aft² × 0.09290304;
Aft² = Am² × 10.7639104167. - Rectangle area (Length × Width):
A = L × W [area derived from dimensions before expressing in ac, ft², m², ha].
Examples.
- Square feet to acres: 18,000 ft² → 18,000 ÷ 43,560 = 0.41322 ac (≈ 1,672.25 m²).
- Square feet to hectares: 87,120 ft² → 87,120 × 0.09290304 ÷ 10,000 = 0.809 ha (≈ 2.0 ac).
- Length × Width (imperial): 150 ft × 90 ft → 13,500 ft² → 0.3100 ac (≈ 1,254.19 m²).
Corresponding tools. For the reverse direction use Acres to Square Feet Converter. For metric conversions use Square Feet ⇄ Square Meters or Acres ⇄ Hectares. For dimension-based calculations, see Area (Length × Width) Calculator.
