Convert energy units — joules, kilowatt-hours, calories, BTU, electron volts and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 J | 0.000737561 ft·lb | |
| 0.01 J | 0.00737561 ft·lb | |
| 0.1 J | 0.0737561 ft·lb | |
| 1 J | 0.737561 ft·lb | |
| 5 J | 3.68781 ft·lb | |
| 10 J | 7.37561 ft·lb | |
| 50 J | 36.8781 ft·lb | |
| 100 J | 73.7561 ft·lb | |
| 1000 J | 737.561 ft·lb |
Formula: Foot-Pound = Joule × 0.7376
Multiply any joule value by 0.7376 to get foot-pound.
Reverse: Joule = Foot-Pound × 1.356
Common joule values — factor: 1 J = 0.7376 ft·lb
| Joule (J) | Foot-Pound (ft·lb) | Context |
|---|---|---|
| 0.001 J | 0.0007376 ft·lb | 1 mJ |
| 0.1 J | 0.07376 ft·lb | Heartbeat |
| 1 J | 0.7376 ft·lb | Lift apple 10cm |
| 4.184 J | 3.086 ft·lb | 1 calorie |
| 100 J | 73.76 ft·lb | Sprinting 1 sec |
| 1,000 J | 737.6 ft·lb | 1 kJ |
| 4,184 J | 3,086 ft·lb | 1 kcal food |
| 1e+04 J | 7,376 ft·lb | 10 kJ |
| 1e+05 J | 7.376e+04 ft·lb | 100 kJ |
| 1.055e+06 J | 7.782e+05 ft·lb | 1 BTU |
| 3.6e+06 J | 2.655e+06 ft·lb | 1 kWh |
| 1e+08 J | 7.376e+07 ft·lb | ~100 MJ |
| 1.000e+09 J | 7.376e+08 ft·lb | 1 GJ |
| 1.000e+12 J | 7.376e+11 ft·lb | 1 TJ |
| 1.000e+15 J | 7.376e+14 ft·lb | 1 PJ |
J × 0.7376 = ft·lb. Round to × 0.738.
One joule ≈ three-quarters of a foot-pound.
ft·lb × 1.356 = J.
Uses joules as the SI unit for all energy, work, and heat calculations.
Calculates kinetic energy, potential energy, and work in joules.
Measures reaction enthalpies, bond energies, and heat of solution in joules.
Converts between power (watts) and energy (joules = watt-seconds).
Measures fracture energy and impact resistance in joules.
Applies the first law of thermodynamics with energy in joules.
The joule is the SI derived unit of energy, work, and heat, defined as the energy transferred when a force of one newton moves an object one meter. It was named after James Prescott Joule, the English physicist who established the mechanical equivalent of heat in the 1840s.
The joule is universal in physics and engineering: kinetic energy (½mv²), potential energy (mgh), electrical energy (VIt), and heat are all measured in joules. One joule is the energy needed to lift a 100g apple one meter against gravity.
Interesting fact: The human heart expends about 1 joule of energy with each beat. A 60-watt light bulb uses 60 joules every second. The entire energy released by a 1-megaton nuclear weapon equals about 4.18 × 10¹⁵ joules.
The foot-pound (ft·lb) is an Imperial unit of energy equal to the work done when a force of one pound-force moves an object one foot, equaling 1.35582 joules. It has been used in British and American engineering since the 18th century.
Foot-pounds are standard in US mechanical engineering for torque specifications, engine output (often ft·lb of torque), and ballistic energy measurements. Rifle bullet energies are commonly quoted in foot-pounds in American publications.
Interesting fact: A typical 9mm pistol bullet has about 350 ft·lb of muzzle energy. The torque specification for tightening a car wheel bolt is typically 80–100 ft·lb. One horsepower equals 550 ft·lb per second.
Converting joule to foot-pound is common across energy, nutrition, engineering, and science. Different sectors use different energy units — joules in physics, kcal in nutrition, kWh in electricity, and BTU in HVAC — making accurate conversion essential for cross-disciplinary work and international comparisons.
Quick reference: 5 J = 3.688 ft·lb and 10 J = 7.376 ft·lb. Reverse: 1 ft·lb = 1.356 J. Exact factor: 1 J = 0.7376 ft·lb.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.