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Kilocalories to BTU Converter

Convert Kilocalories (kcal) to BTU (BTU) instantly, or use the conversion table below to look up common values.

1 kcal = 3.965667 BTU

Kilocalories to BTU conversion table

Kilocalories (kcal)BTU (BTU)
13.965667
27.931334
311.897
415.862667
519.828334
1039.656668
2599.141671
50198.283342
100396.566683

How to convert Kilocalories to BTU

1 kcal equals 3.965667 BTU. Use the converter above for any value, or read the table for common conversions.

BTU = kcal × 3.9656668313909194 · kcal = BTU × 0.2521644007217973

Multiply a kilocalories figure by 3.965667 to get btu, or divide it by 0.252164 to go the other way.

Worked examples

  • 1 kcal= 3.965667 BTU
  • 5 kcal= 19.828334 BTU
  • 10 kcal= 39.656668 BTU
  • 100 kcal= 396.566683 BTU
  • 500 kcal= 1,982.833416 BTU

What these units are

Kilocalories (kcal). A kilocalorie is 1,000 calories, or 4,184 joules. It is the 'calorie' on food labels, so a 2,000-calorie diet means 2,000 kilocalories.

BTU (BTU). A BTU (British thermal unit) is 1,055.05585262 joules — the energy needed to heat one pound of water by one degree Fahrenheit. It is used for heating and cooling capacity.

All factors are exact definitions, so only the display is rounded.

Converting Kilocalories to BTU in practice

Working in kilocalories

Exactly 1,000 thermochemical calories, or 4,184 joules, make one kilocalorie. A food label that prints calorie, often with a capital letter, means this unit rather than the small calorie of physics.

Food energy on packaging, diet plans, restaurant menus and sports nutrition is stated in kilocalories. Physiology and nutrition research also reports energy expenditure in the same unit.

Kilocalories convert to kilojoules by the exact factor 4.184, and to joules by 4,184, with no rounding. Since a kilowatt-hour is 3.6 megajoules, one kilocalorie is a little over 0.00116 kilowatt-hours.

The standard mistake is to treat the label's calorie as the small calorie and conclude that food holds far less energy than it does. The label unit is one thousand small calories.

The kilocalorie is the label unit, the calorie is its one-thousandth in physics, and the kilojoule is the metric equivalent at 4.184 kilojoules each. A diet figure and a physics figure therefore need different units before they can be compared.

Checking a kilocalories to btu conversion

Energy units are defined against the joule, so every conversion in this dimension is a single exact multiplication by a published number rather than a chain of steps that could accumulate error.

The pair that needs care is the kilowatt-hour, because it looks like a power unit and is not. It is a watt sustained for an hour, which is why an electricity meter counts in kilowatt-hours while a generator is rated in kilowatts: one is an amount, the other is a rate, and only a duration links them.

To check an energy conversion, express both sides in joules or both in kilowatt-hours before comparing. The commonest mistake is treating a food calorie as a calorie when the label means a kilocalorie, which understates the figure a thousandfold.

Tanzania reference points

Real quantities, converted into the units on this page.

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