A megajoule (MJ) is a metric-prefixed unit of energy equal to 106 joules, using the SI mega prefix.
Megajoules to Kilojoules
Convert Megajoule (MJ) to Kilojoule (kJ) instantly with an exact formula, conversion table, and FAQ.
Reserved for a responsive leaderboard above the conversion details.
Professional calculator style
World-scale conversion engine
30+ categories
6,500+ units
Instant results
Offline ready
Energy calculator
Energy Converter
Convert megajoules (MJ) to kilojoules (kJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A kilojoule (kJ) equals 1,000 joules and is commonly used on nutrition labels outside the United States.
kJ = MJ × 1000
Results update instantly for Megajoules to Kilojoules conversions.
Reserved above the conversion cards and below the converter.
Formula
kJ = MJ × 1000
MJ = kJ × 0.001
Conversion table
| 1 MJ | 1000 kJ |
| 5 MJ | 5000 kJ |
| 10 MJ | 10000 kJ |
| 20 MJ | 20000 kJ |
| 50 MJ | 50000 kJ |
| 100 MJ | 100000 kJ |
| 500 MJ | 500000 kJ |
| 1000 MJ | 1.000000e+06 kJ |
Related conversions
Reserved between the cards and the FAQ so the page stays balanced.
How the formula works
Both megajoule and kilojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in megajoules by 1000 to get kilojoules. To reverse the conversion, multiply a kilojoule value by 0.001 to get back to megajoules.
Frequently asked questions
What is Megajoule (MJ)?
A megajoule (MJ) is a metric-prefixed unit of energy equal to 106 joules, using the SI mega prefix.
What is Kilojoule (kJ)?
A kilojoule (kJ) equals 1,000 joules and is commonly used on nutrition labels outside the United States.
How do I convert megajoules to kilojoules?
Multiply the megajoule value by 1000 to get the equivalent in kilojoules. For example, 5 MJ × 1000 = 5000 kJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1000 is an exact, non-rounded value.
Can I convert kilojoules back to megajoules?
Yes. Divide the kilojoule value by 1000, or multiply it by 0.001, to get megajoules.
Reserved between the FAQ and the article so the page stays balanced.
About converting megajoules to kilojoules
A megajoule (MJ) is a metric-prefixed unit of energy equal to 106 joules, using the SI mega prefix. A kilojoule (kJ) equals 1,000 joules and is commonly used on nutrition labels outside the United States.
Use this calculator to move between megajoules and kilojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.