How many kilojoules are in one joule?

There are 0.001 kilojoules in 1 joule.

How do you convert kilojoules to joules?

Multiply the number of kilojoules by 1,000 — or use the formula J = kJ × 1,000.

What is 6 kilojoules in joules?

6 kilojoules is 6,000 joules. 6 × 1,000 = 6,000 joules.

Is the kilojoules to joules conversion exact?

Yes. The relationship is fixed by definition, so 1,000 is an exact conversion factor — only the displayed result is rounded.

Kilojoules to Joules Converter

Convert kilojoules to joules instantly with this free kilojoules to joules converter. Enter any value to get an accurate energy conversion, plus the formula, the conversion factor and a full reference table.

What is 1 kilojoule in joules?

1 kilojoule is equal to exactly 1,000 joules.

1 × 1,000 = 1,000 joules

Amount

Result1,000

1 kilojoule = 1,000 joules

Kilojoules to Joules formula

J = kJ × 1,000

The kilojoules to joules conversion factor is 1,000, which is exact by definition. 1 kilojoule = 1,000 joules, and 1 joule = 0.001 kilojoules.

Worked examples

2 kilojoules = 2,000 joules — 2 × 1,000 = 2,000 joules
6 kilojoules = 6,000 joules — 6 × 1,000 = 6,000 joules
10 kilojoules = 10,000 joules — 10 × 1,000 = 10,000 joules

Kilojoules to Joules conversion table

Every value below is calculated with the exact conversion factor and rounded for display.

kilojoules to joules conversion table
Kilojoules (kJ)	Joules (J)
1 kJ	1,000 J
2 kJ	2,000 J
3 kJ	3,000 J
4 kJ	4,000 J
5 kJ	5,000 J
6 kJ	6,000 J
7 kJ	7,000 J
8 kJ	8,000 J
9 kJ	9,000 J
10 kJ	10,000 J
12 kJ	12,000 J
15 kJ	15,000 J
20 kJ	20,000 J
25 kJ	25,000 J
30 kJ	30,000 J
50 kJ	50,000 J
75 kJ	75,000 J
100 kJ	100,000 J
500 kJ	500,000 J
1,000 kJ	1,000,000 J

When you need to convert kilojoules to joules

Comparing food energy labelled in calories with labels in kilojoules.
Reading utility bills and appliance ratings that mix kWh, joules and BTU.

Common mistakes to avoid

Dividing when you should multiply. Because 1 kilojoule = 1,000 joules, the answer should be larger than the number you started with.
Rounding too early. Convert first at full precision, then round the final answer to the precision the task actually needs.

How precise does the answer need to be?

Round only at the end, and only to the precision your task actually needs. The converter above keeps full double precision internally and rounds for display.

How these units are defined

Kilojoule (kJ): 1,000 joules; food energy labelling in Australia and New Zealand. This unit's relationship to the SI base unit is exact by definition, so no rounding enters the conversion factor.
Joule (J): The SI unit of energy: one newton-meter. This unit's relationship to the SI base unit is exact by definition, so no rounding enters the conversion factor.

Frequently asked questions

What is 1 kilojoule in joules?: 1 kilojoule is equal to 1,000 joules.
How many kilojoules are in one joule?: There are 0.001 kilojoules in 1 joule.
How do you convert kilojoules to joules?: Multiply the number of kilojoules by 1,000 — or use the formula J = kJ × 1,000.
What is 6 kilojoules in joules?: 6 kilojoules is 6,000 joules. 6 × 1,000 = 6,000 joules.
Is the kilojoules to joules conversion exact?: Yes. The relationship is fixed by definition, so 1,000 is an exact conversion factor — only the displayed result is rounded.