What Is kip?
A kip is a unit that measures force. It is equal to one thousand pounds of force. Engineers use it when they deal with very heavy loads on structures like bridges, tall buildings, and towers.
The word kip is often used in the United States when talking about structural engineering, foundations, and other fields where loads can be very large.
Definition
A kip is a US customary unit of force.
- 1 kip = 1000 pounds of force (1000 lbf)
- In metric terms, 1 kip is about 4.448 kilonewtons (4.448 kN)
Important note. A kip measures force, not mass or weight as a pure number. It tells how strongly something pushes or pulls on a structure because of gravity or other loads.
History / Origin
The name kip comes from the idea of a kilo pound. Kilo means one thousand, so a kip is one thousand pounds of force.
Engineers began using the term in the 1900s. It helped them write large forces in a shorter and clearer way. Instead of 120000 pounds of force, they could write 120 kips.
Because many early engineering standards and building codes in the United States used the pound and not the newton, the kip became a handy step between pounds and the very large forces found in real structures.
Symbol & Abbreviation
The most common symbols and short forms for the kip are.
- kip or kips when written as a word.
- kip or kipf when showing force, where f reminds us it is force.
- Sometimes klb is also used, which stands for kilo pound.
In many structural drawings or tables you will see values like 25 kip or 25 kips to show total load, and sometimes kip ft for moment or bending values.
Current Use Around the World
The kip is still used today, but mostly in certain places and fields.
- United States. Common in structural engineering, civil engineering, and geotechnical work such as pile loads and soil pressure.
- Some other countries. Used only when reading or copying American standards, design manuals, or machine ratings.
- International work. Most modern projects outside the US use the SI unit of force, the newton, and larger forces in kilonewtons or meganewtons.
Even inside the US, many newer codes also give values in kilonewtons. However, kips are still very common in design offices, calculation sheets, and older textbooks.
Example Conversions
Here are some simple conversion examples using the kip.
Between kip and pound force
- 1 kip = 1000 lbf
- 5 kips = 5 × 1000 lbf = 5000 lbf
- 0.5 kip = 0.5 × 1000 lbf = 500 lbf
Between kip and newton
1 pound of force is about 4.448 newtons. So.
- 1 kip = 1000 lbf × 4.448 N per lbf ≈ 4448 N
- 1 kip ≈ 4.448 kN
Sample problems
- If a column carries 40 kips, that is 40 × 1000 = 40000 lbf, which is about 40 × 4.448 = 178 kN.
- If a beam reaction is 12 kips, that is 12 × 1000 = 12000 lbf or about 12 × 4.448 = 53.4 kN.
Related Units
The kip is related to several other force units.
- Pound force (lbf). The basic US customary unit of force. 1 kip = 1000 lbf.
- Newton (N). The SI base unit of force. 1 kip ≈ 4448 N.
- Kilonewton (kN). Equal to 1000 N. 1 kip ≈ 4.448 kN.
- Tonne force or metric ton force. About 9.807 kN. 1 kip is a bit less than half a tonne of force.
Engineers often move between kips and kilonewtons, because many design tables come in both systems.
FAQs
Is a kip a unit of mass or weight
A kip is a unit of force, not mass. It describes how strongly something pushes or pulls. In everyday talk people may say weight, but in science it is force.
Why do engineers use kips instead of pounds
On big projects, forces can be in the tens or hundreds of thousands of pounds. Writing these numbers in kips makes drawings and calculations cleaner and easier to read.
Is the kip an SI unit
No. The official SI unit of force is the newton. The kip is part of the US customary system and is not an SI unit.
Where will I see kips used
You will most likely see kips in American structural engineering drawings, bridge plans, building codes, foundation reports, and some machinery load ratings.
How do I convert from kips to kilonewtons quickly
You can use this shortcut. multiply kips by 4.45 to get kilonewtons. For example, 10 kips × 4.45 ≈ 44.5 kN.
Is kip the same as kilopound
Yes in common engineering use, kip and kilopound both mean one thousand pounds of force. The word kip is simply shorter and easier to say.