Joules to Calories, Kilowatt-hours & BTU Converter
This free online energy converter converts between Joule, Kilojoule, Calorie, Kilocalorie, Watt-hour, Kilowatt-hour, and BTU. Enter a value in any field and the result updates instantly — no sign-up, no ads blocking the tool, and it runs entirely in your browser.
Type a number into any unit field above and every other field recalculates automatically. All conversions use standard, internationally recognized conversion factors.
Quick Reference
| 1 Joule | = | 0.001 Kilojoule |
| 1 Joule | = | 0.239006 Calorie |
| 1 Joule | = | 0.000239 Kilocalorie |
| 1 Joule | = | 0.000278 Watt-hour |
| 1 Joule | = | 2.77778e-07 Kilowatt-hour |
| 1 Joule | = | 0.000948 BTU |
Frequently Asked Questions
How many Kilojoule are in 1 Joule?
1 Joule equals 0.001 Kilojoule.
How many Calorie are in 1 Joule?
1 Joule equals 0.239006 Calorie.
How many Kilocalorie are in 1 Joule?
1 Joule equals 0.000239 Kilocalorie.