Energy · canonical reference
Energy conversion table
A compact cross-unit reference for the most useful energy units. Values are computed from the same unit registry used by the interactive pair converters, so the family table and exact calculator routes cannot silently drift apart.
One-unit matrix
What 1 unit equals
Read across a row as “1 row unit equals the value shown in the column unit.” Temperature rows use the exact Celsius/Fahrenheit/Kelvin relationships rather than a simple multiplicative factor.
| 1 unit | J | kJ | kWh | kcal | BTU |
|---|---|---|---|---|---|
| 1 Joules | 1 | 0.001 | 0.0000002778 | 0.0002390057 | 0.0009478171 |
| 1 Kilojoules | 1,000 | 1 | 0.0002777778 | 0.2390057361 | 0.9478171203 |
| 1 Kilowatt-hours | 3,600,000 | 3,600 | 1 | 860.4206500956 | 3,412.1416331279 |
| 1 Kilocalories | 4,184 | 4.184 | 0.0011622222 | 1 | 3.9656668314 |
| 1 British thermal units | 1,055.05585262 | 1.0550558526 | 0.0002930711 | 0.2521644007 | 1 |
Common values
Common joules conversions
Use the table for quick lookups, then open the exact interactive converter when you need a custom value, reverse direction, formula guide, saved setup, shareable state or local batch CSV.
| Joules | Kilojoules | Kilowatt-hours | Kilocalories | British thermal units |
|---|---|---|---|---|
| 1 J | 0.001 kJ | 0.0000002778 kWh | 0.0002390057 kcal | 0.0009478171 BTU |
| 2 J | 0.002 kJ | 0.0000005556 kWh | 0.0004780115 kcal | 0.0018956342 BTU |
| 5 J | 0.005 kJ | 0.0000013889 kWh | 0.0011950287 kcal | 0.0047390856 BTU |
| 10 J | 0.01 kJ | 0.0000027778 kWh | 0.0023900574 kcal | 0.0094781712 BTU |
| 25 J | 0.025 kJ | 0.0000069444 kWh | 0.0059751434 kcal | 0.023695428 BTU |
| 50 J | 0.05 kJ | 0.0000138889 kWh | 0.0119502868 kcal | 0.047390856 BTU |
| 100 J | 0.1 kJ | 0.0000277778 kWh | 0.0239005736 kcal | 0.094781712 BTU |
All canonical units
7 units in this family
Joules (J) · Kilojoules (kJ) · Kilowatt-hours (kWh) · Calories (cal) · Kilocalories (kcal) · British thermal units (BTU) · Foot-pounds (ft⋅lb)
Truth boundary
Reference, not measurement advice.
The table performs deterministic mathematical conversion only. It does not establish measurement accuracy, calibration, suitability, legal metrology or domain-specific tolerance.
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