British Thermal Unit to Kilocalorie Converter
Energy · unit-converter
Convert British Thermal Unit to Kilocalorie with fixed input and output units, a step-by-step formula line, and reference tables. Factors are joule-based; food energy uses thermochemical calories. The full Energy Converter also includes MMBtu, toe, thermal kWh, and MeV/GeV.
Calculator
From: British Thermal Unit (btu)
To: Kilocalorie (kcal)
About British Thermal Unit
The British thermal unit used here is the IT BTU: ≈ 1,055.056 J. It appears in HVAC, heating equipment, and US engineering data.
About Kilocalorie
The kilocalorie (kcal) is 1,000 calories in the nutrition sense—often labeled “Calorie” on food packaging. Here 1 kcal = 4,184 J (thermochemical calorie definition used in this tool).
How to convert british thermal units to kilocalories
1 british thermal unit is equal to 0.2521644007218 kilocalorie when both are expressed in joule-equivalents:
1 btu = (1,055.05585262 J ÷ 4,184 J) kcal = 0.2521644007218 kcal
Each british thermal unit is defined as 1,055.05585262 J and each kilocalorie as 4,184 J in this tool, so one btu equals 1,055.05585262 ÷ 4,184 kcal = 0.2521644007218 kcal.
Let d(btu) be the numeric amount in British Thermal Unit (btu), and d(kcal) the amount in Kilocalorie (kcal). Then:
d(kcal) = d(btu) × (1,055.05585262 / 4,184)
Equivalently, divide by how many btu fit into one kcal (joules per kcal divided by joules per btu):
d(kcal) = d(btu) ÷ 3.96566683139092
Or: kilocalorie = british thermal unit ÷ 3.96566683139092
Examples
Example #1: Convert 1 btu to kilocalorie
1 btu = 1 btu × (1,055.05585262/4,184) kcal = 0.2521644007 kcal
1 btu = 1 btu ÷ 3.96566683139092 = 0.2521644007 kcal
Example #2: Convert 10 btu to kilocalorie
10 btu = 10 btu × (1,055.05585262/4,184) kcal = 2.5216440072 kcal
10 btu = 10 btu ÷ 3.96566683139092 = 2.5216440072 kcal
Summary
To convert British Thermal Unit to Kilocalorie, multiply the value in btu by the ratio of joules per btu divided by joules per kcal. Equivalently: value_kcal = value_btu × (1055.05585262 / 4184). Numerically, 1 btu equals 0.2521644007217973 kcal.
Relationship context
You are converting between US / imperial engineering units (BTU, therm, ft·lb) (British Thermal Units) and food / nutrition energy (calories) (Kilocalories). All values are mapped through joules first. The numeric factor is 2.521644e-1.
Conversion tables
| British Thermal Unit (btu) | Kilocalorie (kcal) |
|---|---|
| 0.1 | 0.0252164401 |
| 1 | 0.2521644007 |
| 2 | 0.5043288014 |
| 3 | 0.7564932022 |
| 4 | 1.0086576029 |
| 5 | 1.2608220036 |
| 6 | 1.5129864043 |
| 7 | 1.765150805 |
| 8 | 2.0173152058 |
| 9 | 2.2694796065 |
| British Thermal Unit (btu) | Kilocalorie (kcal) |
|---|---|
| 10 | 2.5216440072 |
| 20 | 5.0432880144 |
| 30 | 7.5649320216 |
| 40 | 10.0865760289 |
| 50 | 12.6082200361 |
| 60 | 15.1298640433 |
| 70 | 17.6515080505 |
| 80 | 20.1731520577 |
| 90 | 22.694796065 |
| 100 | 25.2164400722 |