Area Converter.

Convert between square millimetres, centimetres, metres, kilometres, inches, feet, acres and hectares.

mm²
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cm²
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Reference Table

mm² cm² m² km² in² ft² yd² ac ha
0.10.0011.000000e-71.000000e-130.00015500030.00000107641.195990e-72.471054e-111.000000e-11
10.010.0000011.000000e-120.00155000310.00001076390.0000011962.471054e-101.000000e-10
100.10.000011.000000e-110.0155000310.00010763910.00001195992.471054e-91.000000e-9
10010.00011.000000e-100.155000310.0010763910.0001195992.471054e-81.000000e-8
1000100.0011.000000e-91.5500030.01076391040.001195992.471054e-71.000000e-7
100001000.011.000000e-815.5000310.10763910420.01195990050.00000247110.000001
10000010000.11.000000e-7155.000311.0763910.11959900460.00002471050.00001

Units in this converter

mm²Sq. Millimetre
cm²Sq. Centimetre
1 mm² = 0.01cm²
m²Sq. Metre
1 mm² = 0.000001m²
km²Sq. Kilometre
1 mm² = 1.0000e-12km²
in²Sq. Inch
1 mm² = 0.00155in²
ft²Sq. Foot
1 mm² = 0.00001076ft²
yd²Sq. Yard
1 mm² = 0.0000012yd²
acAcre
1 mm² = 2.4711e-10ac
haHectare
1 mm² = 1.0000e-10ha

Understanding area conversion

An area converter changes a surface measurement from one unit into another — square feet to square metres, or acres to hectares. It comes up constantly in property listings, floor plans, land records and gardening, where the same plot may be quoted in square feet by an agent, square metres on a drawing and acres in the title deed. This tool covers metric units (mm², cm², m², km²), imperial units (in², ft², yd²) and the two land-measure units, the acre and the hectare.

The formula. Every value passes through one base unit, the square metre. Because area is a length squared, each factor is the length factor squared: 1 ft² = 0.09290304 m² (that is 0.3048², since 1 ft = 0.3048 m), 1 in² = 0.00064516 m², 1 yd² = 0.83612736 m², 1 acre = 4,046.86 m² and 1 hectare = 10,000 m² exactly. A value is multiplied to square metres, then divided by the target unit's factor: result = value × factor(from) ÷ factor(to).

Worked example. A plot measuring 30 ft × 40 ft is 1,200 ft². Multiplying by 0.09290304 gives 111.48 m². Since 1 acre is 43,560 ft², the same plot is 1,200 ÷ 43,560 ≈ 0.0275 acres. Going the other way, a 2-hectare farm is 20,000 m², or about 4.94 acres.

Where it's used. Area conversion runs through real estate and construction: Indian property is advertised in square feet while approvals are filed in square metres, farmland is recorded in acres in the US and UK but hectares across most of Europe, and carpet, tile and paint are all sold by coverage area. A doubling of a room's linear dimensions quadruples its area — the squared factors are exactly why estimates go wrong when units are mixed.

How to convert area units

  1. Choose the unit you are converting from. This converter covers 9 units: mm², cm², m², km² and 5 more.
  2. Choose the unit you want in the second dropdown, or press the swap button to reverse the direction.
  3. Type your value. The result updates as you type; there is no calculate button.
  4. Use Copy to take the number, or Share to send a link with your value already filled in.

Frequently Asked Questions

How many square feet are in a square metre?

One square metre is about 10.7639 square feet. The factor is the length factor squared: 1 ft = 0.3048 m, so 1 ft² = 0.3048² = 0.09290304 m², and dividing 1 by that gives 10.7639.

How many square feet are in an acre?

An acre is exactly 43,560 square feet, or about 4,046.86 square metres. It originally described the land one ox team could plough in a day — a strip one furlong long by one chain wide.

What is the difference between an acre and a hectare?

A hectare is a metric unit equal to 10,000 square metres — a square 100 m on each side. An acre is about 4,046.86 m², so 1 hectare ≈ 2.471 acres. Hectares are standard across Europe and in most land records outside the US and UK.

Why does doubling a room’s dimensions quadruple its area?

Because area is a length multiplied by a length. A 3 m × 4 m room is 12 m²; doubling both sides to 6 m × 8 m gives 48 m² — four times as much, not twice. This is also why every area conversion factor is a length factor squared, and why mixing units in a floor-area estimate goes wrong so quickly.

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