Calories to BTU converter

To convert calories to BTU, enter the value in the first field. The result in BTU is calculated automatically using the exact conversion factor.

1 cal ≈ 0.00396566683139 BTU
1 BTU ≈ 252.164400722 cal

Formula: BTU ≈ cal × 0.00396566683139
cal ≈ BTU × 252.164400722

Definitions: 1 cal = 4.184 J; 1 BTU = 1055.05585262 J

The calorie (cal) here is the thermochemical calorie, exactly 4.184 joules, roughly the energy needed to raise one gram of water by one degree Celsius. It is used in chemistry and physics and should not be confused with the food Calorie, which is a kilocalorie.

The British thermal unit (BTU) here is the International Table BTU, about 1,055 joules, roughly the energy needed to raise one pound of water by one degree Fahrenheit. It is used in the United States for heating and cooling equipment, fuel content and natural gas.

See the conversion table with commonly used values, handy for quick reference or study.