Btu to Kj ConverterRight in Your Browser
Convert British thermal units (BTU) to kilojoules (kJ). The BTU rates air conditioners, furnaces and grills in the US — the heat to warm a pound of water by one degree Fahrenheit. The kilojoule (kJ) is 1,000 joules — the energy unit on food labels in Australia, New Zealand and much of Europe. Everything is calculated locally in your browser — no server, and it works offline.
1.05506 kJ
in kilojoules (kilojoule)
To convert British thermal units to kilojoules, multiply the British thermal unit value by 1.05506.
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| British thermal units (BTU) | Kilojoules (kJ) |
|---|---|
| 1 | 1.05506 |
| 2 | 2.11011 |
| 3 | 3.16517 |
| 4 | 4.22022 |
| 5 | 5.27528 |
| 10 | 10.5506 |
| 20 | 21.1011 |
| 50 | 52.7528 |
| 100 | 105.506 |
Frequently Asked Questions
How many kilojoules are in a British thermal unit?
One British thermal unit equals 1.05506 kilojoules (1 BTU = 1.05506 kJ). So to go from British thermal units to kilojoules, multiply the British thermal unit value by 1.05506.
What is the formula to convert British thermal units to kilojoules?
To convert British thermal units to kilojoules, multiply the British thermal unit value by 1.05506. For example, 10 BTU is 10.5506 kJ.
What is 12000 British thermal units in kilojoules?
12000 British thermal units — a small window air conditioner's rating — is 12660.7 kilojoules. The converter above works for any value, entirely in your browser.
Is the British thermal unit to kilojoule conversion exact?
The factor used here is the defined value: 1 BTU = 1.055055853 kJ. Results are rounded to six significant digits for readability, so for high-precision work use the full factor. This uses the International Table BTU (exactly 1.05505585262 kJ), the definition behind HVAC ratings; the thermochemical BTU is about 0.07% smaller.
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