Viscosity
in²/stoSt
Convert square inches per second (in²/s) to stokes (St).
Factor1 in²/s = 6.4516 St
Converter
in²/s
Accepts numbers or expressions, e.g. 150 + 14.7
Result
St
Rendered to 6 significant figures.
Formula
Formula
St = in²/s × 6.4516
Multiply any value in square inches per second by 6.4516 to obtain the value in stokes.
Worked example
Convert 1 in²/s to St.
- 01Start with 1 in²/s.
- 02Multiply by the conversion factor: 1 × 6.4516 = 6.4516 St.
Result1 in²/s = 6.4516 St
Conversion table
| in²/s | St |
|---|---|
| 1 | 6.4516 |
| 2 | 12.903 |
| 5 | 32.258 |
| 10 | 64.516 |
| 20 | 129.03 |
| 50 | 322.58 |
| 100 | 645.16 |
| 200 | 1290.3 |
| 500 | 3225.8 |
| 1000 | 6451.6 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from in²/s to St?
1 in²/s equals 6.4516 St. To convert, multiply the value in square inches per second by 6.4516.
How do I convert 1 in²/s to St?
1 in²/s = 6.4516 St. For any value, multiply by 6.4516.
How do I convert St back to in²/s?
Divide by the same factor — or equivalently, multiply by 0.1550003. So 1 St = 0.155 in²/s.
When would I need to convert square inch per second to stoke?
Kinematic viscosity conversions between in²/s and St 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).