Centijoule is 0.01 joule units.
Centijoules to BTU Converter — cJ to BTU
Convert Centijoule (cJ) to BTU (BTU) using the exact conversion factor (1 centijoule = 0.0000094782 btu). See the formula, worked examples, conversion table, history, and common uses.
Centijoules to BTU converter
Converter
Energy Converter
Convert joules, calories, kilowatt-hours, BTU, electronvolts, therms, and mechanical work units.
British thermal unit.
Result = input x 0.01 / 1055.055853.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Centijoules to BTU
Centijoule and BTU both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Specifically: Centijoule is 0.01 joule units, and british thermal unit.
Formula
btu = centijoules × 0.00000947817120313
This factor comes from each unit's defined relationship to the category's base unit: 1 centijoule equals 0.01 base units, and 1 btu equals 1055.05585262 base units, so dividing one by the other gives the direct centijoule-to-btu factor of 0.00000947817120313.
Simple example
1 cJ × 0.000009478171203 = 0.0000094782 BTU
1 centijoule = 0.0000094782 btu.
Real-world example
100 cJ × 0.000009478171203 = 0.0009478171 BTU
100 centijoules = 0.0009478171 btu.
Conversion table
| Centijoule (cJ) | BTU (BTU) |
|---|---|
| 1 cJ | 0.0000094782 BTU |
| 10 cJ | 0.0000947817 BTU |
| 100 cJ | 0.0009478171 BTU |
| 500 cJ | 0.0047390856 BTU |
| 1,000 cJ | 0.0094781712 BTU |
| 2,000 cJ | 0.0189563424 BTU |
Reverse conversion: BTU to Centijoule
0.0000094782 BTU × 105505.5853 = 1.000003038 cJ
0.0000094782 btu = 1.000003038 centijoules.
centijoules = btu × 105505.585262
For a page dedicated to this direction, see BTU to Centijoule.
Understanding the Centijoule (cJ)
Centijoule is 0.01 joule units.
Understanding the BTU
BTU (BTU) measures energy. A British thermal unit is defined as exactly 1,055.05585262 joules (the International Table BTU). It is classified as a US customary unit.
Where it's used: United States (HVAC, heating, and appliance energy ratings)
Uses of the BTU today
- Air conditioner and furnace capacity ratings in the US
- Water heater and appliance energy specifications
- US energy industry (natural gas is often billed via BTU content)
History of the BTU
The BTU originated in 19th-century steam engineering as the heat needed to raise one pound of water by one degree Fahrenheit, paralleling the calorie's metric definition. Several slightly different BTU values existed historically before the 'International Table' BTU was standardized at exactly 1,055.05585262 joules.
Historical origin. BTU was not the invention of a single named person; it developed through the process described above.
BTU — sources
- NIST Special Publication 811 — Documents the International Table BTU's exact joule equivalence.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many btu are in 1 centijoule?
1 centijoule equals 0.0000094782 btu, using the exact defined conversion factor rather than an estimate.
How do I convert centijoule to btu?
Multiply the centijoule value by 0.000009478171203. The converter above does this instantly to whatever precision you set.
How do I convert btu back to centijoule?
Use the reverse factor: 1 btu equals 105,505.5853 centijoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a centijoule?
Centijoule (cJ) is a unit of energy.
What is a btu?
BTU (BTU) measures energy. A British thermal unit is defined as exactly 1,055.05585262 joules (the International Table BTU). It is classified as a US customary unit.
Is the centijoule to btu conversion exact?
Yes. A British thermal unit is defined as exactly 1,055.05585262 joules (the International Table BTU). That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.