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Convert Foot-pound to Kilojoule

Please provide values below to convert foot-pound [ft*lbf] to kilojoule [kJ], or vice versa.

From: foot-pound
To: kilojoule


Definition: A foot-pound (ft·lb or ft·lbf) is a unit of work or energy in the imperial and United States customary systems of units. It is defined as the energy transferred when a force of one pound-force is applied over a linear displacement of one foot.

History/origin: The foot-pound is an English Engineering unit that is part of the British Gravitational system, based on the foot-pound-second (FPS) system. The FPS system is built using the units of foot for length, avoirdupois pound for mass or force, and the second for time.

Current use: The foot-pound is used in countries that have not adopted the International System of Units (SI). The United States is one of the largest countries where the foot-pound is still used in certain applications, though even in the US, the joule is preferred in most scientific contexts.


Definition: The kilojoule is an SI (International System of Units) derived unit of energy that is equal to 1000 joules. The joule is defined as the amount of energy transferred to an object when a one newton force acts on an object in the direction movement through a distance of one meter.

History/origin: The kilojoule, like other SI derived units, uses SI prefixes to denote multiples or submultiples of the given unit. In this case, the prefix "kilo" is used to express a multiple of 1000.

Current use: In countries that have adopted SI, the kilojoule is widely used as a unit of food energy. In some cases, both kilojoules and kilocalories are displayed, though in countries such as the United States, only kilocalories are shown (often referred to as "Calories") on food labels. Aside from this everyday use, kilojoules are used within scientific contexts around the world.

Foot-pound to Kilojoule Conversion Table

Foot-pound [ft*lbf]Kilojoule [kJ]
0.01 ft*lbf1.35582E-5 kJ
0.1 ft*lbf0.0001355818 kJ
1 ft*lbf0.0013558179 kJ
2 ft*lbf0.0027116359 kJ
3 ft*lbf0.0040674538 kJ
5 ft*lbf0.0067790897 kJ
10 ft*lbf0.0135581795 kJ
20 ft*lbf0.027116359 kJ
50 ft*lbf0.0677908974 kJ
100 ft*lbf0.1355817948 kJ
1000 ft*lbf1.3558179483 kJ

How to Convert Foot-pound to Kilojoule

1 ft*lbf = 0.0013558179 kJ
1 kJ = 737.5621493 ft*lbf

Example: convert 15 ft*lbf to kJ:
15 ft*lbf = 15 × 0.0013558179 kJ = 0.0203372692 kJ

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