Hectares to Acres

Cadastral Metrology & NIST SP 811 Standards

The Hectare (ha) is an SI-accepted metric unit of land area equal to a square measuring 100 meters on each side. An Acre is an imperial land measure defined as 43,560 square feet.

Primary Land Area Multipliers

• 1 Hectare (ha): 10,000 m^2 = 2.471054 Acres = 107,639 sq ft = 0.01 km^2

• 1 Acre (ac): 43,560 sq ft = 4,046.856 m^2 = 0.404686 Hectares = (1) / (640) sq mi

• 1 Square Kilometer: = 100 Hectares = 247.105 Acres

• 1 Square Mile: = 640 Acres = 258.999 Hectares

Equations

• Acres = Hectares × 2.47105381

• Hectares = Acres × 0.40468564

How to Use This Calculator

Enter your Land Area to Convert (e.g. 10.0) and Conversion Direction — choose from Hectares to Acres (ha → ac / multiply by 2.471), Acres to Hectares (ac → ha / divide by 2.471). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Conversion factors used in this calculator:

1 Hectare = 10,000 m2

Worked Example

A 10-hectare agricultural farm property measures 24.711 acres (100,000 square meters), equivalent in area to approximately 18.7 regulation American football fields.

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.