Convert 21 hectares to square miles

How many square miles are 21 hectares?

Answer: 0.0811
hectares (ha)
{"answerString":"0.081","answerSymbol":"square miles"}
21 hectares = 0.081 square miles

Precise decimal and fraction answers

The conversion in square miles rounded to six significant decimal places is 21 ha = 0.0810815 sq mi. The precise fraction answer is 5887/72606 sq mi.

Decimal Precision

Conversion from one to ten decimal places

  • 21 ha = 0.08 sq mi
  • 21 ha = 0.081 sq mi
  • 21 ha = 0.0811 sq mi
  • 21 ha = 0.08108 sq mi
  • 21 ha = 0.081081 sq mi
  • 21 ha = 0.0810815 sq mi
  • 21 ha = 0.08108145 sq mi
  • 21 ha = 0.081081453 sq mi
  • 21 ha = 0.0810814533 sq mi
  • 21 ha = 0.08108145329 sq mi

Hectares to square miles conversion factor and formulas

Formula

The conversion factor between hectares and square miles is 258.999. This represents the ratio of hectares per one square mile. To calculate the value in square miles, we can either divide by the conversion factor or multiply by its inverse.

Division

To convert from hectares to square miles, divide hectares by 258.999.
The formula is expressed as:
ha ÷ 258.999 = sq mi

Multiplication

Alternatively we can multiply by the inverse conversion factor to get the same result.
The inverse of 258.999 is 1/258.999 or 0.004. To convert from hectares to square miles, multiply hectares by 0.004.
The formula is expressed as:
ha × 0.004 = sq mi

To convert 21 hectares to square miles, divide 21 hectares by 258.999.
21 ha ÷ 258.999 = 0.081 sq mi

How large are 21 hectares?

Real world scale examples to visualize the area of 21 hectares / 0.081 square miles

  • 3.96 times the area of the base of the Great Pyramid of Giza (53,000 sq-m)
  • 43% of the area of Vatican City (490,000 sq-m)
  • 34% of the square footage of the Pentagon (6,600,000 sq-ft)

About this conversion

Converting hectares to square miles is a conversion between units from separate unit systems - hectares are metric (SI) defined units while square miles are US Customary / UK Imperial .

About Hectares

SI Unit

The hectare is a metric measure of area defined by a square with sides 100 meters in length. One hundred hectares equal a square kilometer. The unit is widely used in the measure of large areas of land. While it is not an official SI unit, the hectare is fully compatible with the metric system and used in most countries which have adopted metric units.

Reverse this conversion

Convert from square miles to hectares instead.

21 hectares to other area units

Metric

  • 21 ha = 21 ha
  • 21 ha = 0.21 km2
  • 21 ha = 210,000 m2
  • 21 ha = 2.1×107 dm2
  • 21 ha = 2.1×109 cm2
  • 21 ha = 2.1×1011 mm2
  • 21 ha = 2.1×1017 µ2
  • 21 ha = 2.1×1023 nm2

Imperial/U.S.

  • 21 ha = 51.892 acre
  • 21 ha = 0.081 sq mi
  • 21 ha = 251,157.91 sq yd
  • 21 ha = 2,260,421.188 sq ft
  • 21 ha = 3.255×108 sq in

References and Citations

  1. International Bureau of Weights and Measures (BIPM) The International System of Units (SI)
  2. National Institute of Standards and Technology (NIST) General Tables of Units of Measurement

Decimal conversions for 21 ha to sq mi

ha sq mi
21.01 ha 0.081 sq mi
21.02 ha 0.081 sq mi
21.03 ha 0.081 sq mi
21.04 ha 0.081 sq mi
21.05 ha 0.081 sq mi
21.06 ha 0.081 sq mi
21.07 ha 0.081 sq mi
21.08 ha 0.081 sq mi
21.09 ha 0.081 sq mi
21.1 ha 0.081 sq mi
21.11 ha 0.082 sq mi
21.12 ha 0.082 sq mi
21.13 ha 0.082 sq mi
21.14 ha 0.082 sq mi
21.15 ha 0.082 sq mi
21.16 ha 0.082 sq mi
21.17 ha 0.082 sq mi
21.18 ha 0.082 sq mi
21.19 ha 0.082 sq mi
21.2 ha 0.082 sq mi
21.21 ha 0.082 sq mi
21.22 ha 0.082 sq mi
21.23 ha 0.082 sq mi
21.24 ha 0.082 sq mi
21.25 ha 0.082 sq mi
21.26 ha 0.082 sq mi
21.27 ha 0.082 sq mi
21.28 ha 0.082 sq mi
21.29 ha 0.082 sq mi
21.3 ha 0.082 sq mi
21.31 ha 0.082 sq mi
21.32 ha 0.082 sq mi
21.33 ha 0.082 sq mi
21.34 ha 0.082 sq mi
21.35 ha 0.082 sq mi
21.36 ha 0.082 sq mi
21.37 ha 0.083 sq mi
21.38 ha 0.083 sq mi
21.39 ha 0.083 sq mi
21.4 ha 0.083 sq mi
21.41 ha 0.083 sq mi
21.42 ha 0.083 sq mi
21.43 ha 0.083 sq mi
21.44 ha 0.083 sq mi
21.45 ha 0.083 sq mi
21.46 ha 0.083 sq mi
21.47 ha 0.083 sq mi
21.48 ha 0.083 sq mi
21.49 ha 0.083 sq mi
21.5 ha 0.083 sq mi
ha sq mi
21.51 ha 0.083 sq mi
21.52 ha 0.083 sq mi
21.53 ha 0.083 sq mi
21.54 ha 0.083 sq mi
21.55 ha 0.083 sq mi
21.56 ha 0.083 sq mi
21.57 ha 0.083 sq mi
21.58 ha 0.083 sq mi
21.59 ha 0.083 sq mi
21.6 ha 0.083 sq mi
21.61 ha 0.083 sq mi
21.62 ha 0.083 sq mi
21.63 ha 0.084 sq mi
21.64 ha 0.084 sq mi
21.65 ha 0.084 sq mi
21.66 ha 0.084 sq mi
21.67 ha 0.084 sq mi
21.68 ha 0.084 sq mi
21.69 ha 0.084 sq mi
21.7 ha 0.084 sq mi
21.71 ha 0.084 sq mi
21.72 ha 0.084 sq mi
21.73 ha 0.084 sq mi
21.74 ha 0.084 sq mi
21.75 ha 0.084 sq mi
21.76 ha 0.084 sq mi
21.77 ha 0.084 sq mi
21.78 ha 0.084 sq mi
21.79 ha 0.084 sq mi
21.8 ha 0.084 sq mi
21.81 ha 0.084 sq mi
21.82 ha 0.084 sq mi
21.83 ha 0.084 sq mi
21.84 ha 0.084 sq mi
21.85 ha 0.084 sq mi
21.86 ha 0.084 sq mi
21.87 ha 0.084 sq mi
21.88 ha 0.084 sq mi
21.89 ha 0.085 sq mi
21.9 ha 0.085 sq mi
21.91 ha 0.085 sq mi
21.92 ha 0.085 sq mi
21.93 ha 0.085 sq mi
21.94 ha 0.085 sq mi
21.95 ha 0.085 sq mi
21.96 ha 0.085 sq mi
21.97 ha 0.085 sq mi
21.98 ha 0.085 sq mi
21.99 ha 0.085 sq mi

Similar ha to sq mi conversions

Frequent conversions from hectares

ha to sq mi ha to sq ft ha to km2 ha to m2 ha to acre