Convert Square inches per second to Centistokes

Convert Square inches per second (in²/s) to Centistokes (cSt) instantly and accurately.

Square inches per second (in²/s)
Centistokes (cSt)

Conversion Formula

cSt = in²/s × 645.16

About Square inches per second

The square inch per second (in²/s) equals 0.0254² = 6.4516 × 10⁻⁴ m²/s. It is the coherent FPS kinematic unit based on the inch, found in US fluid power, hydraulics, and bearing-design references. 1 in²/s = 645.16 cSt = 6.4516 St.

About Centistokes

The centistoke (cSt) equals 10⁻⁶ m²/s = 1 mm²/s. It is the dominant unit for kinematic viscosity in industry worldwide. ASTM D445, ISO 3104, and ACEA lubricant specifications all use cSt. Water at 20 °C ≈ 1.004 cSt; diesel at 40 °C: 2.0-4.5 cSt; SAE 40 oil at 100 °C: 12.5-16.3 cSt. 1 cSt = 10⁻² St.

Quick Reference Table

Square inches per second (in²/s)Centistokes (cSt)
1 in²/s645.16 cSt
2 in²/s1290.32 cSt
5 in²/s3225.8 cSt
10 in²/s6451.6 cSt
25 in²/s16129 cSt
50 in²/s32258 cSt
100 in²/s64516 cSt

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