Torque Converter
Foot-pound (ft·lbf)
Definition: The foot-pound force (symbol: ft·lbf or ft-lb) is an imperial and US customary unit of torque. It is the torque created by one pound-force acting at a perpendicular distance of one foot from a pivot point.
History/origin: This unit originated in the British Empire as part of the foot-pound-second (FPS) system of units. It was the primary measurement for torque during the rise of the American automotive industry.
Current use: Foot-pounds are extensively used in the United States and the UK for automotive engine ratings and manual labor involving torque wrenches.
Inch-pound (in·lbf)
Definition: The inch-pound force (symbol: in·lbf) is a unit of torque equal to one pound-force applied to a moment arm of one inch.
History/origin: As a smaller subdivision of the foot-pound, this unit was developed to provide higher precision for small-scale mechanical assemblies where foot-pounds resulted in fractions that were hard to read.
Current use: Used primarily for low-torque applications such as bicycle maintenance, assembling delicate electronic housings, and medical device manufacturing.
Foot-pound (ft·lbf) to Inch-pound (in·lbf) Conversion Table
| Foot-pound (ft·lbf) [ftlbf] | Inch-pound (in·lbf) [inlbf] |
|---|---|
| 0.01 ftlbf | 0.12 inlbf |
| 0.1 ftlbf | 1.2 inlbf |
| 1 ftlbf | 12.00000002 inlbf |
| 2 ftlbf | 24.00000004 inlbf |
| 3 ftlbf | 36.00000005 inlbf |
| 5 ftlbf | 60.00000009 inlbf |
| 10 ftlbf | 120.00000018 inlbf |
| 20 ftlbf | 240.00000035 inlbf |
| 50 ftlbf | 600.00000089 inlbf |
| 100 ftlbf | 1200.00000177 inlbf |
| 1000 ftlbf | 12000.0000177 inlbf |
How to Convert Foot-pound (ft·lbf) to Inch-pound (in·lbf)
1 ftlbf = 12.00000002 inlbf
1 inlbf = 0.08333333 ftlbf
Example: convert 15 ftlbf to inlbf:
15 ftlbf = 15 × 12.00000002 inlbf = 180.00000027 inlbf
Did You Know?
- In the United States, foot-pounds (ft-lb) is the primary unit used to measure the tightening of bolts on car wheels and engines. Using a torque wrench ensures you don't snap the bolt!
- Inch-pounds are used for delicate tasks, such as working on bicycle components, small electronics, or aerospace parts where high precision is required to avoid damaging threads.