A single PSI, or "pound-per-square-inch," is the measure of force applied to a single square inch of flat surface. More accurately described as "pound-force per-square-inch," as single PSI represents one pound of pressure applied on one square inch of surface. A KPI, stands for "Kilo-pounds-per-inch." More accurately, KPI should be displayed as KPSI, or "kilo-pounds per-square-inch." A single "KPSI," is the measure of "kilo" of pounds per square inch, or 1000 pounds per square inch.

Determine the PSI to be converted. PSI can be used to measure gas pressure, gravitational pressure or pressure of objects pressing against other objects.

Divide the PSI value by 1000 to calculate the KPI, better known as the "KPSI." For example, if the PSI value is 45, the KPSI value is 0.045. A PSI value of 6700 will have a KPSI value of 6.7.

Convert KSPI to PSI by reversing the process. Multiply the KPSI value by 1000 to derive the PSI value. For example, a KPSI value of 1 will have a PSI value of 1000.

Report the findings with the value following by the unit. For example a KPSI value of 6.7 should be reported as "6.7KPSI." A PSI value of 490 is reported as "490 PSI."