processconvert
Permeability

mDtoD

Convert millidarcy (mD) to darcy (D).

Factor1 mD = 0.001 D

Converter

mD

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

Result
1D

Rendered to 6 significant figures.

Formula

Formula
D = mD × 0.001

Multiply any value in millidarcy by 0.001 to obtain the value in darcy.

Worked example

Convert 1000 mD to D.

  1. 01Start with 1000 mD.
  2. 02Multiply by the conversion factor: 1000 × 0.001 = 1 D.
Result1000 mD = 1 D

Conversion table

mDD
10.001
20.002
50.005
100.01
200.02
500.05
1000.1
2000.2
5000.5
10001

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from mD to D?
1 mD equals 0.001 D. To convert, multiply the value in millidarcy by 0.001.
How do I convert 1 mD to D?
1 mD = 0.001 D. For any value, multiply by 0.001.
How do I convert D back to mD?
Divide by the same factor — or equivalently, multiply by 1000. So 1 D = 1000 mD.
When would I need to convert millidarcy to darcy?
Permeability conversions between mD and D 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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