Square Millimeter per Second (mm²/s)
The square millimetre per second (mm²/s) is 10⁻⁶ m²/s and exactly equal to one centistokes. ISO viscosity grades are defined in mm²/s at 40 °C.
Symbol: mm²/s (ASCII: mm2/s)
Quantity: kinematic viscosity (dynamic viscosity divided by density)
SI relation: 1 mm²/s = 0.000001 m²/s (exact)
Derivation: 1 mm²/s = 10⁻⁶ m²/s = 1 cSt
Exact: yes, by definition
Same quantity as centistokes (cSt) : the factor between them is exactly 1.
Typical uses
- Lubricant ISO VG grades (VG 32, 46, 68 …)
- Fuel specifications (diesel 2–4.5 mm²/s at 40 °C)
- Oil analysis reports
Convert square millimeters per second to other units
| Conversion | 1 mm²/s equals | Reverse |
|---|---|---|
| square millimeter per second to centistokes | 1 cSt | centistokes to square millimeter per second |
| square millimeter per second to square meter per second | 0.000001 m²/s | square meter per second to square millimeter per second |
| square millimeter per second to stokes | 0.01 St | stokes to square millimeter per second |
| square millimeter per second to square foot per second | 0.00001076391042 ft²/s | square foot per second to square millimeter per second |
| square millimeter per second to square centimeter per second | 0.01 cm²/s | square centimeter per second to square millimeter per second |
Open the Kinematic Viscosity Converter 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 2 with SI prefix milli.
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 Millimeter per Second (mm²/s). Retrieved October 17, 2026, from https://scientificconverters.com/units/square-millimeter-per-second/
IEEE
Scientific Converters, "Square Millimeter per Second (mm²/s)," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/units/square-millimeter-per-second/