Square Micrometre (µm²)
The square micrometre is the SI-friendly replacement for the darcy, since 1 D = 0.9869233 µm²: reservoir engineers outside the US increasingly quote permeability in µm² or mD.
Symbol: µm² (ASCII: um2)
Quantity: intrinsic permeability of a porous medium
SI relation: 1 µm² = 1 × 10⁻¹² m² (exact)
Derivation: 1 µm² = 10⁻¹² m², almost exactly one darcy (1 D = 0.9869 µm²).
Exact: yes, by definition
Typical uses
- Petroleum reservoir data in SI
- Rock and core analysis
Convert square micrometres to other units
| Conversion | 1 µm² equals | Reverse |
|---|---|---|
| square micrometre to square metre | 1 × 10⁻¹² m² | square metre to square micrometre |
| square micrometre to darcy | 1.013249966 D | darcy to square micrometre |
| square micrometre to millidarcy | 1013.249966 mD | millidarcy to square micrometre |
| square micrometre to square centimetre | 1 × 10⁻⁸ cm² | square centimetre to square micrometre |
Open the Permeability Converter (Darcy, Millidarcy, m²) to convert any value between all units.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 4 (derived units) and Table 8 (non-SI units accepted for use with the SI).
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Square Micrometre (µm²). Retrieved October 29, 2026, from https://scientificconverters.com/units/square-micrometer/
IEEE
Scientific Converters, "Square Micrometre (µm²)," scientificconverters.com. Accessed: Oct. 29, 2026. [Online]. Available: https://scientificconverters.com/units/square-micrometer/