Convert joules to kilojoules

1 J = 0.001 kJ. Change the amount below, or read the formula and the reference table further down.

1 joule equals

0.001kilojoules

1 J = 0.001 kJ

The formula

Joules and kilojoules both measure energy from the same zero, so a single multiplier does the job.

kJ = J × 0.001

Going the other way? Convert kilojoules to joules.

Joules to kilojoules table

Common values, rounded for reading.

Joules (J)Kilojoules (kJ)
10.001
20.002
30.003
40.004
50.005
60.006
70.007
80.008
90.009
100.01
150.015
200.02
250.025
300.03
400.04
500.05
750.075
1000.1
2500.25
5000.5
1,0001

Questions people ask

How many kilojoules are in a joule?
One joule equals 0.001 kilojoules.
How do I convert joules to kilojoules by hand?
Multiply the number of joules by 0.001. For a rough check, 0.001 is close enough for most everyday use.
What is 1 joule in kilojoules?
1 joule is 0.001 kilojoules.

Calcuit generates this page from a unit table, so the factors here match every other page on the site.

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