joules (J)

joules as a conversion hub: 6 direct pairs, all with the exact factor on the page.

Definition1 J = 0.001 kJ exactly

CategoryEnergy Converter

Pairs from here6

Energy Converter

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joules converted to every other unit

J	kJ	cal	kcal	Wh	kWh	Btu
1 J	0.001	0.23900574	0.0002390057	0.0002777778	0.0000002778	0.0009478171
2 J	0.002	0.47801147	0.0004780115	0.0005555556	0.0000005556	0.0018956342
5 J	0.005	1.195029	0.0011950287	0.0013888889	0.0000013889	0.0047390856
10 J	0.01	2.390057	0.0023900574	0.0027777778	0.0000027778	0.0094781712
20 J	0.02	4.780115	0.0047801147	0.0055555556	0.0000055556	0.01895634
50 J	0.05	11.950287	0.01195029	0.01388889	0.0000138889	0.04739086
100 J	0.1	23.900574	0.02390057	0.02777778	0.0000277778	0.09478171

All conversions starting from J

J to kJ J to cal J to kcal J to Wh J to kWh J to Btu

Questions

How do I convert from joules?

Pick the target unit from the table on this page, or open the dedicated pair page — each one carries a converter, a table of common values and the exact factor.

Is joule exact or approximate?

The factor shown (1 J = 0.001 kJ) is fixed by definition, so conversions are exact rather than measured.

What is joule used for?

joules as used in practical measurements