Kilocalories to British thermal units

Type a value in kilocalories to see it in British thermal units straight away, or type in the second box to convert back.

Loading the tool…

Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.

How to use it

  1. Type the value in the kilocalories box.
  2. Read the result in British thermal units as you type, and pick the precision you need.
  3. Swap the direction to convert back, or copy the result.

How it is calculated

BTU = kcal × 3.965666831

Multiply the value in kilocalories by 3.965666831 to get British thermal units.

Example

To convert 25 kcal to British thermal units: 25 × 3.965666831 = 99.1417 BTU.

Conversion table

Kilocalories (kcal)British thermal units (BTU)
13.96567
27.93133
311.897
519.8283
1039.6567
2079.3133
2599.1417
50198.283
100396.567
250991.417
5001,982.83
1,0003,965.67

About the units

Kilocalorie
Equal to 1000 thermochemical calories, exactly 4184 joules. This is the everyday food calorie.
British thermal unit
The imperial unit of heat, using the International Table definition of exactly 1055.05585262 joules. Seen in air conditioner and heater ratings.

Limits and caveats

  • Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
  • Both unit factors are exact by their official definitions.

Questions about this tool

How many British thermal units are in one kilocalorie?

1 kcal = 3.96567 BTU exactly.

How do I convert kilocalories to British thermal units?

Use BTU = kcal × 3.965666831. For example, 25 kcal = 99.1417 BTU.

How many kilocalories are in one British thermal unit?

1 BTU = 0.252164 kcal.

Which calorie do these converters use?

The thermochemical calorie, exactly 4.184 joules, the factor many countries use to turn kcal into kJ on food labels. The International Table calorie is 4.1868 joules, less than 0.07% larger.

What is the difference between kW and kWh?

A kilowatt is a unit of power, the rate of using energy, while a kilowatt-hour is an amount of energy. A 2 kW heater running for three hours uses 6 kWh.