Convert kinematic viscosity units — m²/s, Stokes, centistokes, ft²/s and more.
| Unit | Name | Value |
|---|---|---|
| m²/s | Square Meter/Second | 0.0001 |
| cm²/s | Square Centimeter/Second | 1 |
| cSt | Centistokes | 100 |
| ft²/s | Square Foot/Second | 0.0010763915 |
| in²/s | Square Inch/Second | 0.15500031 |
Formula: m²/s = Stokes × 0.0001
Multiply any Stokes value by 0.0001 to get m²/s.
Reverse: Stokes = m²/s × 1e+04
Water reference (20°C): 0.01004 St = 1.0040e-6 m²/s
Values at ~20°C unless noted. Factor: 1 St = 0.0001 m²/s
| Stokes (St) | m²/s (m²/s) | Fluid |
|---|---|---|
| 0.00015 St | 1.500e-08 m²/s | Air (20°C) |
| 0.005 St | 5.000e-07 m²/s | Petrol (gasoline) |
| 0.01004 St | 1.004e-06 m²/s | Water (20°C) |
| 0.015 St | 1.500e-06 m²/s | Ethanol |
| 0.03 St | 3.000e-06 m²/s | Diesel fuel |
| 0.35 St | 3.500e-05 m²/s | SAE 10W motor oil |
| 0.84 St | 8.400e-05 m²/s | Olive oil |
| 1 St | 1.000e-04 m²/s | SAE 30 motor oil |
| 1.8 St | 0.00018 m²/s | SAE 90 gear oil |
| 14.1 St | 0.00141 m²/s | Glycerin (20°C) |
| 50 St | 0.005 m²/s | Honey |
| 80 St | 0.008 m²/s | Molasses |
| 500 St | 0.05 m²/s | Tomato ketchup |
| 2500 St | 0.25 m²/s | Peanut butter |
| 1.000e+19 St | 1.000e+15 m²/s | Glass (room temp) |
St ÷ 10,000 = m²/s. Exact.
1 St = 10⁻⁴ m²/s. 0.01 St = 10⁻⁶ m²/s (water).
m²/s × 10,000 = St.
Specifies lubricant viscosity grades in cSt at 40°C and 100°C per ISO VG and SAE standards.
Uses kinematic viscosity in cSt for pipeline flow calculations, pump sizing, and heat exchanger design.
Measures crude oil and refined product viscosity in cSt for pipeline transport and refinery design.
Selects hydraulic fluids based on kinematic viscosity in cSt for pump compatibility and system efficiency.
Characterizes food product viscosity (honey, sauces, oils) in cSt for process design and quality control.
Uses ft²/s or cSt for atmospheric kinematic viscosity in Reynolds number calculations for aircraft design.
The Stokes (St) is the CGS unit of kinematic viscosity, equal to exactly 1 cm²/s = 10⁻⁴ m²/s. It was named after Sir George Gabriel Stokes by the British Association for the Advancement of Science in 1882.
The Stokes is used in petroleum engineering and some industrial viscometer specifications. Water at 20°C = 0.01 St = 1 cSt. Engine oils range from 50–200 cSt (0.5–2 St) at 40°C. Pourable molasses is about 5–10 St (500–1,000 cSt).
Interesting fact: George Stokes was also the first to explain fluorescence (Stokes shift), derive the Navier-Stokes equations of fluid motion, and develop the theory of diffraction. His work in fluid mechanics in the 1840s–1850s remains fundamental to modern engineering.
Square meter per second (m²/s) is the SI unit of kinematic viscosity, defined as dynamic viscosity divided by fluid density. It measures how easily a fluid flows under gravity relative to its own inertia. The unit was formalized with SI in 1960.
m²/s values are very small for most fluids: water at 20°C ≈ 1×10⁻⁶ m²/s; air ≈ 1.5×10⁻⁵ m²/s; SAE 30 motor oil ≈ 1×10⁻⁴ m²/s. The large exponents make m²/s impractical for everyday use, which is why cSt and St are more common.
Interesting fact: Kinematic viscosity is the ratio ν = μ/ρ (dynamic viscosity ÷ density). A very viscous but dense fluid can have lower kinematic viscosity than a less viscous but very light fluid — which is why kinematic viscosity (not dynamic) governs flow by gravity.
Kinematic viscosity (ν = μ/ρ) measures how a fluid flows under gravity. The cSt is dominant in industry; m²/s is the SI unit; St and cm²/s are the CGS equivalents. Key anchor: water at 20°C ≈ 1 cSt = 10⁻⁶ m²/s = 0.01 St.
Exact factor: 1 St = 0.0001 m²/s. Reverse: 1 m²/s = 1e+04 St.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.