Viscosity
Sttoin²/s
Convert stokes (St) to square inches per second (in²/s).
Factor1 St = 0.1550003 in²/s
Converter
St
Accepts numbers or expressions, e.g. 150 + 14.7
Result
in²/s
Rendered to 6 significant figures.
Formula
Formula
in²/s = St × 0.1550003
Multiply any value in stokes by 0.1550003 to obtain the value in square inches per second.
Worked example
Convert 10 St to in²/s.
- 01Start with 10 St.
- 02Multiply by the conversion factor: 10 × 0.1550003 = 1.55 in²/s.
Result10 St = 1.55 in²/s
Conversion table
| St | in²/s |
|---|---|
| 1 | 0.155 |
| 2 | 0.31 |
| 5 | 0.775 |
| 10 | 1.55 |
| 20 | 3.1 |
| 50 | 7.75 |
| 100 | 15.5 |
| 200 | 31 |
| 500 | 77.5 |
| 1000 | 155 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from St to in²/s?
1 St equals 0.1550003 in²/s. To convert, multiply the value in stokes by 0.1550003.
How do I convert 1 St to in²/s?
1 St = 0.155 in²/s. For any value, multiply by 0.1550003.
How do I convert in²/s back to St?
Divide by the same factor — or equivalently, multiply by 6.4516. So 1 in²/s = 6.4516 St.
When would I need to convert stoke to square inch per second?
Kinematic viscosity conversions between St and in²/s arise in hydraulic fluid selection, lubricant grading (ISO VG), pipe flow Reynolds number calculations, and fuel-oil specification. Kinematic viscosity equals dynamic viscosity divided by fluid density and cannot be directly compared to dynamic viscosity without that context.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).