Convert Darcy to Millidarcy

Convert Darcy (D) to Millidarcy (mD) instantly and accurately.

Darcy (D)
Millidarcy (mD)

Conversion Formula

mD = D × 1000

About Darcy

The darcy (D) ≈ 9.869 × 10⁻¹³ m², the oilfield-standard permeability unit defined by Darcy's law: 1 D passes 1 cm³/s of 1 cP fluid through 1 cm² cross-section under a 1 atm/cm gradient. Highly permeable consolidated sandstone: 1-5 D; unconsolidated sand: 5-20 D. 1 D = 1 000 mD ≈ 0.9869 µm².

About Millidarcy

The millidarcy (mD) equals 10⁻³ D ≈ 9.869 × 10⁻¹⁶ m², the everyday unit in petroleum reservoir engineering worldwide. Conventional sandstone reservoirs: 1-1 000 mD; carbonate reservoirs: 0.1-100 mD; economic gas recovery typically requires k ≥ 0.1 mD. Permeameter and well-test reports give results in mD. 1 mD = 10⁻³ D = 10³ µD.

Quick Reference Table

Darcy (D)Millidarcy (mD)
1 D1000 mD
2 D2000 mD
5 D5000 mD
10 D10000 mD
25 D25000 mD
50 D50000 mD
100 D100000 mD

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