BTU (IT) to Calories (cal) Converter
Enter a value to instantly convert between energy units.
1 BTU (IT) = 252.1644 Calorie (thermochemical)
Key Formulas
Kilocalorie → Kilojoule
kJ = kcal × 4.184Kilojoule → Kilocalorie
kcal = kJ × 0.239006Kilowatt-Hour → Joule
J = kWh × 3600000Joule → Kilowatt-Hour
kWh = J × 2.77778e-7Formula
cal = BTU × 252.164One BTU (IT) equals 252.164 thermochemical calories. BTU is the standard unit for US heating and cooling equipment, water heaters, and industrial furnaces. Converting to calories is needed when comparing to food energy or nutritional data.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
An energy auditor converting 1 BTU from a furnace spec to cal for comparison with food energy — 252 cal.
1 BTU = 252.16 cal
A boiler rated at 10,000 BTU/h produces 2,521,640 cal/h for the efficiency comparison.
10000 BTU = 2521640 cal
A heating contractor calculating 100 BTU from a space heater reports 25,216 cal in the quote.
100 BTU = 25216.4 cal
A residential furnace rated at 50,000 BTU/h produces 12,608,200 cal/h for the rating.
50000 BTU = 12608200 cal