PSI to Kilopounds Per Square Inch (psi to ksi)
1 pound per square inch equals 0.001 kilopounds per square inch exactly.
How to convert pounds per square inch to kilopounds per square inch
To convert pounds per square inch to kilopounds per square inch, multiply the number of pounds per square inch by 0.001. This factor is exact. To go the other way, multiply kilopounds per square inch by 1,000.
kilopounds per square inch = pounds per square inch × 0.001
Example: 10 pounds per square inch = 0.01 kilopounds per square inch.
About these units
Pound Per Square Inch (psi)
About 6,894.757 pascals. The common unit for tire pressure, hydraulics and gas pipelines in the US.
Unlike most pressure units, psi has no namesake: it simply spells out its own definition, one pound-force acting on one square inch, and it is based on avoirdupois units. Used mainly in the United States, it is about 6.895 kilopascals.
The letters after the unit matter. Psia is measured against a vacuum, while psig is measured against the surrounding air, so at sea level, where the atmosphere is about 14.7 psi, you add that amount to a gauge reading to get an absolute one. A bicycle tire at 65 psig is therefore at 79.7 psia, and the label psid means a difference between two pressures rather than a reference to ambient air.
Typical automobile tires are listed at about 32 psig, and road racing bicycle tires at about 120 psig. One standard atmosphere is 14.696 psi, which gives a feel for how many multiples of sea-level air those tire pressures represent.
1 pound per square inch = 6,894.757293 pascals (approximately).
Sources: Wikipedia: Pounds per square inch; Wikipedia: Standard atmosphere (unit)
Kilopound Per Square Inch (ksi)
1,000 psi (about 6.895 MPa). Used for the strength of materials such as steel in US engineering.
Thousands of pounds per square inch get unwieldy to write, so American engineers shortened them to ksi, the kilopound per square inch. Wikipedia notes it is used mostly in materials science, where tensile strength runs to large numbers of psi. One ksi is 1,000 psi, or about 6.895 MPa; NIST gives 6.894757 MPa.
Steel specifications, reinforced concrete and structural design are the typical uses. A concrete compressive strength of 4 ksi corresponds to about 27.6 MPa, and a bolt rated at 60 ksi would be roughly 414 MPa. The related unit Mpsi, a million psi, is used for elastic moduli of metals, so steel at 200 GPa is about 29 Mpsi. Metric countries write all of this in megapascals, which is why engineers working across borders keep the factor 6.895 close at hand.
1 kilopound per square inch = 6,894,757.293 pascals (approximately).
Sources: Wikipedia: Pounds per square inch; NIST SP 811, Appendix B.8; Wikipedia: Pascal (unit)
Related conversions
- Kilopounds per square inch to PSI (reverse)
- PSI to pascals
- PSI to kilopascals
- PSI to bars
- PSI to standard atmospheres
- PSI to hectopascals
- PSI to megapascals
- PSI to millibars
- PSI to torr
- PSI to millimeters of mercury
- PSI to inches of mercury
- PSI to gigapascals
- PSI to millimeters of water
- Pascals to kilopounds per square inch
- Kilopascals to kilopounds per square inch
- Bars to kilopounds per square inch
- Standard atmospheres to kilopounds per square inch
See all pressure units.