Gigajoule is 1000000000 joule units.
Gigajoules to Kilojoules Converter — GJ to kJ
Convert Gigajoule (GJ) to Kilojoule (kJ) using the exact conversion factor (1 gigajoule = 1,000,000 kilojoule). See the formula, worked examples, and conversion table.
Gigajoules to Kilojoules converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
Kilojoule is 1000 joule units.
Result = input x 1e+9 / 1000.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Gigajoules to Kilojoules
Gigajoule and Kilojoule both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Gigajoule is 1000000000 joule units, and kilojoule is 1000 joule units.
Formula
kilojoules = gigajoules × 1000000
This factor comes from each unit's defined relationship to the category's base unit: 1 gigajoule equals 1000000000 base units, and 1 kilojoule equals 1000 base units, so dividing one by the other gives the direct gigajoule-to-kilojoule factor of 1000000.
Simple example
1 GJ × 1000000 = 1,000,000 kJ
1 gigajoule = 1,000,000 kilojoules.
Real-world example
100 GJ × 1000000 = 100,000,000 kJ
100 gigajoules = 100,000,000 kilojoules.
Conversion table
| Gigajoule (GJ) | Kilojoule (kJ) |
|---|---|
| 1 GJ | 1,000,000 kJ |
| 10 GJ | 10,000,000 kJ |
| 50 GJ | 50,000,000 kJ |
| 100 GJ | 100,000,000 kJ |
| 500 GJ | 500,000,000 kJ |
| 1,000 GJ | 1,000,000,000 kJ |
Reverse conversion: Kilojoule to Gigajoule
1 kJ × 0.000001 = 0.000001 GJ
1 kilojoule = 0.000001 gigajoules.
gigajoules = kilojoules × 0.000001
For a page dedicated to this direction, see Kilojoule to Gigajoule.
Understanding the Gigajoule (GJ)
Gigajoule is 1000000000 joule units.
Understanding the Kilojoule (kJ)
Kilojoule is 1000 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilojoules are in 1 gigajoule?
1 gigajoule equals 1,000,000 kilojoules, using the exact defined conversion factor rather than an estimate.
How do I convert gigajoule to kilojoule?
Multiply the gigajoule value by 1000000. The converter above does this instantly to whatever precision you set.
How do I convert kilojoule back to gigajoule?
Use the reverse factor: 1 kilojoule equals 0.000001 gigajoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a gigajoule?
Gigajoule (GJ) is a unit of engineering.
What is a kilojoule?
Kilojoule (kJ) is a unit of engineering.
Is the gigajoule to kilojoule conversion exact?
Yes. Both gigajoule and kilojoule are defined by fixed standards rather than physical artifacts, so the factor of 1000000 used above is exact to as many digits as you choose to display.
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.