Work from one pound-force over one foot.
Foot-pounds to Calories Converter — ft-lb to cal
Convert Foot-pound (ft-lb) to Calorie (cal) using the exact conversion factor (1 foot-pound = 0.3240482668 calorie). See the formula, worked examples, conversion table, history, and common uses.
Foot-pounds to Calories converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
A thermochemical calorie is 4.184 joules.
Result = input x 1.355817948 / 4.184.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Foot-pounds to Calories
Foot-pound and Calorie both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Work from one pound-force over one foot, and a thermochemical calorie is 4.184 joules.
Formula
calories = foot-pounds × 0.32404826681
This factor comes from each unit's defined relationship to the category's base unit: 1 foot-pound equals 1.35581794833 base units, and 1 calorie equals 4.184 base units, so dividing one by the other gives the direct foot-pound-to-calorie factor of 0.32404826681.
Simple example
1 ft-lb × 0.3240482668 = 0.3240482668 cal
1 foot-pound = 0.3240482668 calories.
Real-world example
100 ft-lb × 0.3240482668 = 32.40482668 cal
100 foot-pounds = 32.40482668 calories.
Conversion table
| Foot-pound (ft-lb) | Calorie (cal) |
|---|---|
| 1 ft-lb | 0.3240482668 cal |
| 10 ft-lb | 3.240482668 cal |
| 50 ft-lb | 16.20241334 cal |
| 100 ft-lb | 32.40482668 cal |
| 500 ft-lb | 162.0241334 cal |
| 1,000 ft-lb | 324.0482668 cal |
Reverse conversion: Calorie to Foot-pound
0.3240482668 cal × 3.085960033 = 1 ft-lb
0.3240482668 calories = 1 foot-pounds.
foot-pounds = calories × 3.08596003258
For a page dedicated to this direction, see Calorie to Foot-pound.
Understanding the Foot-pound (ft-lb)
Work from one pound-force over one foot.
Understanding the Calorie
Calorie (cal) measures energy. The thermochemical calorie used in this converter is defined as exactly 4.184 joules. It is classified as a Non-SI unit (limited use with SI).
Where it's used: Nutrition labeling in the US and several other countries still commonly uses the kilocalorie (as 'Calorie')
Calorie vs. Calorie (kilocalorie). Food labels' capitalized 'Calorie' is actually one kilocalorie (1,000 small calories) — a long-standing labeling convention that causes frequent confusion.
Uses of the Calorie today
- Food energy labeling (as kilocalories, often written 'Calories')
- Historical chemistry and thermodynamics contexts
History of the Calorie
The calorie was originally defined in the early 19th century as the heat needed to raise one gram of water by one degree Celsius, but different scientific traditions defined it at slightly different reference temperatures, producing several close but non-identical 'calorie' values historically (15 °C calorie, mean calorie, thermochemical calorie).
To resolve this ambiguity, the thermochemical calorie was fixed by convention at exactly 4.184 joules; the very similar International Table calorie is fixed at exactly 4.1868 joules. The nutritional 'Calorie' seen on food labels is actually a kilocalorie (1,000 calories).
Historical origin. Calorie was not the invention of a single named person; it developed through the process described above.
Calorie — sources
- NIST Special Publication 811 — Documents the thermochemical calorie's exact joule equivalence.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many calories are in 1 foot-pound?
1 foot-pound equals 0.3240482668 calories, using the exact defined conversion factor rather than an estimate.
How do I convert foot-pound to calorie?
Multiply the foot-pound value by 0.3240482668. The converter above does this instantly to whatever precision you set.
How do I convert calorie back to foot-pound?
Use the reverse factor: 1 calorie equals 3.085960033 foot-pounds. You can also use the swap control in the converter above to flip the direction instantly.
What is a foot-pound?
Foot-pound (ft-lb) is a unit of engineering.
What is a calorie?
Calorie (cal) measures energy. The thermochemical calorie used in this converter is defined as exactly 4.184 joules. It is classified as a Non-SI unit (limited use with SI).
Is the foot-pound to calorie conversion exact?
Yes. The thermochemical calorie used in this converter is defined as exactly 4.184 joules. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between calorie vs. calorie (kilocalorie)?
Food labels' capitalized 'Calorie' is actually one kilocalorie (1,000 small calories) — a long-standing labeling convention that causes frequent confusion.