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Permeability

mm²toft²

Convert square millimetres (permeability) (mm²) to square feet (permeability) (ft²).

Factor1 mm² = 1.076391e-5 ft²

Converter

mm²

Accepts numbers or expressions, e.g. 150 + 14.7

Result
1.07639ft²

Rendered to 6 significant figures.

Formula

Formula
ft² = mm² × 1.076391e-5

Multiply any value in square millimetres (permeability) by 1.076391e-5 to obtain the value in square feet (permeability).

Worked example

Convert 100000 mm² to ft².

  1. 01Start with 100000 mm².
  2. 02Multiply by the conversion factor: 100000 × 1.076391e-5 = 1.07639 ft².
Result100000 mm² = 1.07639 ft²

Conversion table

mm²ft²
11.0764e-5
22.1528e-5
55.382e-5
100.00010764
200.00021528
500.0005382
1000.0010764
2000.0021528
5000.005382
10000.010764

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from mm² to ft²?
1 mm² equals 1.076391e-5 ft². To convert, multiply the value in square millimetres (permeability) by 1.076391e-5.
How do I convert 1 mm² to ft²?
1 mm² = 1.07639e-5 ft². For any value, multiply by 1.076391e-5.
How do I convert ft² back to mm²?
Divide by the same factor — or equivalently, multiply by 92903.04. So 1 ft² = 92903 mm².
When would I need to convert square millimetre (permeability) to square foot (permeability)?
Permeability conversions between mm² and ft² appear in petroleum and reservoir engineering, hydrogeology, geotechnical engineering, packed-bed filtration and porous-materials research. The darcy (D) and its sub-multiples (mD, µD, nD) dominate petroleum-engineering documentation; SI area-equivalent units (m², µm², mm², cm², ft²) appear in geophysics and porous-media research. Intrinsic permeability is a property of the porous medium alone — this category does NOT include hydraulic conductivity (m/s, requires fluid density and viscosity), gas permeability (Klinkenberg slip corrections) or membrane-permeability coefficients, all of which are different physical quantities and require explicit assumptions.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).

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