Foot-Pound Force (ft·lbf) to Kilojoules (kJ) Converter
Enter a value to instantly convert between energy units.
1 Foot-Pound Force = 0.0014 Kilojoule
Key Formulas
Kilocalorie → Kilojoule
kJ = kcal × 4.184Kilojoule → Kilocalorie
kcal = kJ × 0.239006Kilowatt-Hour → Joule
J = kWh × 3600000Joule → Kilowatt-Hour
kWh = J × 2.77778e-7Formula
kJ = ft·lbf × 0.001355818One foot-pound force equals 0.001356 kilojoules (1.356 joules). The ft·lbf is the imperial mechanical energy unit for torque, work, and power specifications in US engineering. Kilojoules are the SI standard. Converting ft·lbf to kJ is essential when translating US machinery specifications to international engineering standards or SI-based simulations.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
SI equivalent: 738.255 ft·lbf = exactly 1 kJ — conversion constant for engineering reports.
738.255 ft·lbf = 1 kJ
A hydraulic press does 1,000 ft·lbf of work per cycle — 1.356 kJ per stroke — used in industrial load calculations.
1000 ft·lbf = 1.356 kJ
A wrench applies 500 ft·lbf of torque — 0.678 kJ of rotational work — standard fastener spec converted to SI.
500 ft·lbf = 0.678 kJ
A large turbine accumulates 100,000 ft·lbf of rotor energy — 135.6 kJ — for the ISO technical report.
100000 ft·lbf = 135.58 kJ