Glossary

Kip is an engineering unit of force equal to 1,000 pounds-force. The word comes from “kilo-pound,” with “kilo” meaning one thousand. In structural, construction, mechanical, and fastener applications, kips are used as a convenient way to express large loads without writing lots of zeros.

For example, instead of saying a bolt is carrying 25,000 lb of tension, an engineer may say it is carrying 25 kips. The conversion is:

1 kip = 1,000 lbf

So:

10 kips = 10,000 lbf
50 kips = 50,000 lbf
0.5 kip = 500 lbf

In fastener and bolted-joint work, kips may be used to describe tensile load, clamp load, proof load, preload, shear load, structural load, or testing force. For example, a heavy structural bolt might be tested or specified by the number of kips it can carry before yielding, proof loading, or failure.

Kip is also closely related to ksi, which means kips per square inch. Since one kip equals 1,000 pounds-force, 1 ksi = 1,000 psi. So a steel with a tensile strength of 120 ksi has a tensile strength of 120,000 psi.

In simple terms, a kip is just a cleaner way to talk about big forces. Instead of saying “thirty-six thousand pounds of force,” you can say 36 kips and keep the math from looking like a runaway freight train.

Kips per square inch (KSI) is a unit of measurement used to express the strength of materials. One kip equals 1,000 pounds of force, meaning 1 ksi is equal to 1,000 pounds per square inch (psi). In the fastener industry, ksi is commonly used to specify mechanical properties such as tensile strength, yield strength, and proof load. For example, a fastener with a tensile strength of 60 ksi can withstand 60,000 pounds of force per square inch before failure.