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Convert Joules to Foot-pounds

Joule (J) to Foot-pound (ft·lb) unit conversion — enter any value below to get an instant result, or use the table for common values.

Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.

The numeric value you want to convert. Decimals are accepted.

Result

1 Joule = 0.73756215 Foot-pounds

1 Foot-pound = 1.3558179 Joules

1 J in every supported unit

Conversion chart: Joule to Foot-pounds

Conversion table

Joule (J) Foot-pound (ft·lb)
0.01 J 0.0073756215 ft·lb
0.1 J 0.073756215 ft·lb
1 J 0.73756215 ft·lb
2 J 1.4751243 ft·lb
3 J 2.2126864 ft·lb
5 J 3.6878107 ft·lb
10 J 7.3756215 ft·lb
20 J 14.751243 ft·lb
50 J 36.878107 ft·lb
100 J 73.756215 ft·lb
1000 J 737.56215 ft·lb

Joule (J)

Definition: The SI derived unit of energy, defined as the work done when a force of one newton moves an object one meter in the direction of that force (1 J = 1 N·m = 1 kg·m²/s²).

History: Named after English physicist James Prescott Joule, whose 1840s experiments established the mechanical equivalent of heat and helped formalize the law of conservation of energy. The unit was formally adopted into the metric system at the second General Conference on Weights and Measures in 1889.

Current use: The universal base unit of energy in physics, chemistry, and engineering worldwide, used for everything from the kinetic energy of a moving car to the energy released in a chemical reaction.

Foot-pound (ft·lb)

Definition: The energy transferred when a force of one pound-force acts through a distance of one foot, equal to about 1.356 joules.

History: A natural byproduct of the imperial system's foot-and-pound base units, it became the standard energy and work unit in English and American engineering and mechanics well before the metric system was adopted for scientific use.

Current use: Used today mainly to express torque and mechanical work in US engineering contexts, such as the tightening specification for bolts or the energy rating of a swinging hammer or falling weight.

Supported Units

Unit Symbol In Joules
Joule J 1 J
Kilojoule kJ 1000 J
Calorie cal 4.184 J
Kilocalorie kcal 4184 J
Watt-hour Wh 3600 J
Kilowatt-hour kWh 3600000 J
British Thermal Unit BTU 1055.0559 J
Foot-pound ft·lb 1.3558179 J
Electronvolt eV 1.60218E-19 J
Erg erg 1E-07 J

About These Parameters

Value
The amount of energy you want to convert, expressed in the "From" unit. Accepts decimals — enter a food label's Calorie count, an electricity bill's kWh reading, or any other energy figure.
From Unit
The unit your input value is currently measured in — for example, kilocalorie if you're starting from a nutrition label, or kilowatt-hour if you're starting from a power bill.
To Unit
The unit you want the result converted into. Use the swap button to flip From and To instantly.

How Energy Conversion Works

The Formula

Every unit here is defined by a fixed multiplier relative to the joule. To convert a value from one unit to another:

result = value × (factor of "From" unit ÷ factor of "To" unit)

For Joule → Foot-pound: multiply by 0.73756215. For example, 1 J × 0.73756215 = 0.73756215 ft·lb.

Why "Calorie" vs. "calorie" Causes Confusion

The small calorie (cal) is the energy needed to raise one gram of water by one degree Celsius — but the "Calorie" printed on a US nutrition label is actually a kilocalorie (kcal), exactly 1,000 times larger. The convention of capitalizing "Calorie" to mean kilocalorie dates back to 19th-century nutrition science and has stuck ever since, so a food listed as "200 Calories" really contains 200,000 small calories. A typical 2,000 kcal daily diet is equal to 8,368 kilojoules — the figure printed on nutrition labels in most countries outside the US.

From Electronvolts to Kilowatt-hours: The Scale of Energy

Because every unit here reduces to the joule, this converter spans an enormous range of physical scales on a single page — from the electronvolt (about 1.6 x 10⁻¹⁹ J, the energy of a single accelerated electron, used in particle physics) up to the kilowatt-hour (3.6 million J, the energy a typical US household uses in roughly an hour of running several appliances at once, and the unit electricity bills are calculated in). An average American home uses on the order of 28-30 kWh per day, which works out to over 100 billion billion electronvolts — a useful reminder of just how small atomic-scale energies really are.

Example

1 J equals 0.73756215 ft·lb. For scale, that's about 0× a typical 2,000 kcal daily diet (2,000 kcal, or 8368000 J).

Frequently Asked Questions

How many Foot-pounds are in 1 Joule?

1 Joule (J) equals exactly 0.73756215 Foot-pounds (ft·lb).

Why is a food Calorie 1,000 times a scientific calorie?

Early nutrition scientists in the late 1800s, including Wilbur Atwater, found the small calorie produced awkwardly large numbers when describing food energy, so they adopted the kilocalorie instead and capitalized it as "Calorie" to distinguish it in writing. The capitalization convention was widely lost in casual use, which is why "200 Calories" on a label actually means 200,000 of the small scientific calories (cal).

How many kWh does an average home use?

A typical US household uses roughly 28-30 kilowatt-hours per day, or around 850-900 kWh per month, though this varies significantly with climate, home size, and appliance efficiency — electric heating, air conditioning, and water heaters are usually the largest contributors.

How accurate are these conversions?

Every conversion factor used here is the exact, internationally defined value (e.g. 1 calorie = exactly 4.184 joules, 1 BTU = exactly 1,055.05585262 joules) — results are limited only by floating-point display precision, not by rounded conversion constants.

Convert Joule to Other Energy Units

Possible Energy Conversions

Electronvolt to Kilowatt-hours British Thermal Unit to Watt-hours Electronvolt to Foot-pounds Kilojoule to Joules Watt-hour to Ergs British Thermal Unit to Kilowatt-hours Foot-pound to Joules Electronvolt to British Thermal Units British Thermal Unit to Foot-pounds Kilowatt-hour to Ergs Erg to Watt-hours Electronvolt to Watt-hours Erg to Joules Erg to Foot-pounds Calorie to Ergs Joule to British Thermal Units Kilowatt-hour to Joules Kilocalorie to Electronvolts Joule to Calories Kilocalorie to Foot-pounds Watt-hour to Foot-pounds Erg to Kilowatt-hours Electronvolt to Joules Watt-hour to Kilowatt-hours Kilocalorie to British Thermal Units Foot-pound to Kilojoules British Thermal Unit to Joules British Thermal Unit to Kilocalories British Thermal Unit to Ergs Electronvolt to Ergs Erg to Electronvolts Calorie to Kilowatt-hours Erg to British Thermal Units Kilocalorie to Calories Kilocalorie to Kilojoules Watt-hour to Calories Calorie to Kilocalories Erg to Kilocalories Kilojoule to Kilocalories Kilocalorie to Watt-hours Watt-hour to British Thermal Units Kilojoule to Watt-hours Kilojoule to Calories British Thermal Unit to Calories Foot-pound to Calories Kilocalorie to Kilowatt-hours Kilowatt-hour to Watt-hours Joule to Ergs Kilowatt-hour to Foot-pounds Kilojoule to Ergs British Thermal Unit to Kilojoules Electronvolt to Kilojoules Joule to Kilocalories Kilojoule to British Thermal Units Kilojoule to Foot-pounds Joule to Kilowatt-hours Foot-pound to British Thermal Units Watt-hour to Kilocalories Calorie to British Thermal Units Calorie to Joules Foot-pound to Kilowatt-hours Kilocalorie to Ergs Electronvolt to Calories Kilowatt-hour to Kilojoules Calorie to Foot-pounds Joule to Watt-hours Calorie to Watt-hours Watt-hour to Joules Kilowatt-hour to Kilocalories Joule to Foot-pounds Electronvolt to Kilocalories British Thermal Unit to Electronvolts Kilowatt-hour to Calories Calorie to Electronvolts Erg to Calories Erg to Kilojoules Kilocalorie to Joules Foot-pound to Electronvolts Foot-pound to Kilocalories Kilojoule to Electronvolts Joule to Electronvolts Watt-hour to Electronvolts Kilowatt-hour to British Thermal Units Kilowatt-hour to Electronvolts Foot-pound to Watt-hours Calorie to Kilojoules Joule to Kilojoules Watt-hour to Kilojoules Foot-pound to Ergs Kilojoule to Kilowatt-hours

See also