Convert kinematic viscosity units — m²/s, Stokes, centistokes, ft²/s and more.
| Unit | Name | Value |
|---|---|---|
| m²/s | Square Meter/Second | 0.092903 |
| cm²/s | Square Centimeter/Second | 929.03 |
| St | Stokes | 929.03 |
| cSt | Centistokes | 92903 |
| in²/s | Square Inch/Second | 143.99994 |
Formula: Centistokes = ft²/s × 9.29e+04
Multiply any ft²/s value by 9.29e+04 to get Centistokes.
Reverse: ft²/s = Centistokes × 1.0764e-5
Water reference (20°C): 1.0807e-5 ft²/s = 1.004 cSt
Values at ~20°C unless noted. Factor: 1 ft²/s = 9.29e+04 cSt
| ft²/s (ft²/s) | Centistokes (cSt) | Fluid |
|---|---|---|
| 1.615e-07 ft²/s | 0.015 cSt | Air (20°C) |
| 5.382e-06 ft²/s | 0.5 cSt | Petrol (gasoline) |
| 1.081e-05 ft²/s | 1.004 cSt | Water (20°C) |
| 1.615e-05 ft²/s | 1.5 cSt | Ethanol |
| 3.229e-05 ft²/s | 3 cSt | Diesel fuel |
| 0.0003767 ft²/s | 35 cSt | SAE 10W motor oil |
| 0.0009042 ft²/s | 84 cSt | Olive oil |
| 0.001076 ft²/s | 100 cSt | SAE 30 motor oil |
| 0.001938 ft²/s | 180 cSt | SAE 90 gear oil |
| 0.01518 ft²/s | 1410 cSt | Glycerin (20°C) |
| 0.05382 ft²/s | 5000 cSt | Honey |
| 0.08611 ft²/s | 8000 cSt | Molasses |
| 0.5382 ft²/s | 5e+04 cSt | Tomato ketchup |
| 2.691 ft²/s | 2.5e+05 cSt | Peanut butter |
| 1.076e+16 ft²/s | 1.000e+21 cSt | Glass (room temp) |
ft²/s × 92,903 = cSt.
1 ft²/s = 929 St = 92,903 cSt. Very large — rarely seen.
cSt × 1.076×10⁻⁵ = ft²/s.
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.
Square foot per second (ft²/s) is the Imperial kinematic viscosity unit, equal to 0.0929 m²/s = 929 St. It is used in US aerospace and some civil engineering contexts where the foot-pound-second system is standard.
ft²/s appears in some US military fluid specifications and older aerospace engineering handbooks. Water at 20°C ≈ 1.075×10⁻⁵ ft²/s. Air ≈ 1.57×10⁻⁴ ft²/s. The large scaling factor (1 ft²/s = 929 St) makes it impractical for most engineering use.
Interesting fact: The kinematic viscosity of the atmosphere at different altitudes is important for aircraft design — Reynolds number calculations use kinematic viscosity. The US Standard Atmosphere tables list kinematic viscosity in ft²/s at each altitude for use in US aerospace engineering.
The centistokes (cSt) equals 0.01 Stokes = 10⁻⁶ m²/s and is the most widely used unit for specifying lubricant and fuel viscosity in industry. Water at 20°C has a kinematic viscosity of almost exactly 1 cSt — making it the universal reference.
cSt is the standard unit in lubricant specifications worldwide: ISO viscosity grades (ISO VG 32, 46, 68, 100, etc.) are defined at 40°C in cSt; SAE engine oil grades correlate to cSt at 100°C; ASTM fuel standards specify viscosity in cSt. Virtually every technical datasheet for oils, lubricants, and fuels uses cSt.
Interesting fact: Water's kinematic viscosity of ~1 cSt at 20°C is the reason the centistokes became so practically useful — the reference value is 1, making quick mental comparisons straightforward. Motor oils are typically 30–100 cSt at 40°C; glycerin is about 1,400 cSt; liquid honey 2,000–10,000 cSt.
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 ft²/s = 9.29e+04 cSt. Reverse: 1 cSt = 1.0764e-5 ft²/s.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.