BTU to Kilojoules Converter
BTUs are how America sizes air conditioners, heaters, and grills, while kilojoules are the metric energy unit engineers and nutritionists use. Converting BTU to kilojoules bridges US appliance shopping with international specs: that 12,000 BTU window unit is about 12,661 kJ/h of cooling. One BTU equals 1.05506 kilojoules — multiply BTUs by 1.05506. The BTU itself is defined as the energy needed to heat one pound of water by one degree Fahrenheit, a thoroughly practical origin for an imperial unit. The converter above gives instant two-way results, the table lists standard appliance ratings, and the FAQs decode the BTU figures on store shelves.
BTU to kJ Calculator
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Quick Reference Table
| BTUs (BTU) | Kilojoules (kJ) |
|---|---|
| 1 | 1.0551 |
| 2 | 2.1101 |
| 3 | 3.1652 |
| 4 | 4.2202 |
| 5 | 5.2753 |
| 6 | 6.3303 |
| 7 | 7.3854 |
| 8 | 8.4404 |
| 9 | 9.4955 |
| 10 | 10.5506 |
| 5000 | 5275.2793 |
| 9000 | 9495.5027 |
| 18000 | 18991.0053 |
| 24000 | 25321.3405 |
Frequently Asked Questions
How many kilojoules are in 12000 btus?
12000 btus = 12660.6702 kilojoules. Just apply the conversion to any value with the converter above.
What is the formula to convert btus to kilojoules?
To convert btus to kilojoules, multiply the number of BTUs by 1.05506. In short: 1 BTU = 1.05506 kJ.
What is a 12,000 BTU air conditioner in kJ?
12,000 BTU equals 12,660.7 kJ — the classic ‘one-ton’ window AC unit. Multiply 12000 × 1.0550558526 = 12660.67 kJ. Enter 12000 in the converter to confirm.
How do I convert kilojoules back to btus?
Simply reverse the math: to go from kilojoules to btus, divide the kilojoules by 1.055056. Or use our dedicated Kilojoules to BTUs converter.