An erg is a CGS energy unit.
Ergs to Kilojoules Converter — erg to kJ
Convert Erg (erg) to Kilojoule (kJ) using the exact conversion factor (1 erg = 1e-10 kilojoule). See the formula, worked examples, and conversion table.
Ergs to Kilojoules converter
Converter
Scientific Units Converter
Convert SI derived units, scientific notation-friendly units, atomic units, and lab measurements.
Context values
Some unit families need one extra value for a physically accurate result.
Kilojoule is 1000 joule units.
Result = input x 1e-7 / 1000.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Ergs to Kilojoules
Erg and Kilojoule are both scientific-measurement units, spanning everything from atomic and laboratory scales to astronomical distances — the kind of conversion that comes up constantly in physics, chemistry, and astronomy when a result needs to move between conventions used in different subfields. Specifically: An erg is a CGS energy unit, and kilojoule is 1000 joule units.
Formula
kilojoules = ergs × 1e-10
This factor comes from each unit's defined relationship to the category's base unit: 1 erg equals 1e-7 base units, and 1 kilojoule equals 1000 base units, so dividing one by the other gives the direct erg-to-kilojoule factor of 1e-10.
Simple example
1 erg × 1e-10 = 1e-10 kJ
1 erg = 1e-10 kilojoules.
Real-world example
10 erg × 1e-10 = 1e-9 kJ
10 ergs = 1e-9 kilojoules.
Conversion table
| Erg (erg) | Kilojoule (kJ) |
|---|---|
| 0.001 erg | 1e-13 kJ |
| 0.01 erg | 1e-12 kJ |
| 1 erg | 1e-10 kJ |
| 10 erg | 1e-9 kJ |
| 100 erg | 1e-8 kJ |
| 1,000 erg | 1e-7 kJ |
Reverse conversion: Kilojoule to Erg
1e-10 kJ × 10000000000 = 1 erg
1e-10 kilojoules = 1 ergs.
ergs = kilojoules × 10000000000
For a page dedicated to this direction, see Kilojoule to Erg.
Understanding the Erg (erg)
An erg is a CGS energy unit.
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 erg?
1 erg equals 1e-10 kilojoules, using the exact defined conversion factor rather than an estimate.
How do I convert erg to kilojoule?
Multiply the erg value by 1e-10. The converter above does this instantly to whatever precision you set.
How do I convert kilojoule back to erg?
Use the reverse factor: 1 kilojoule equals 10,000,000,000 ergs. You can also use the swap control in the converter above to flip the direction instantly.
What is a erg?
Erg (erg) is a unit of scientific units.
What is a kilojoule?
Kilojoule (kJ) is a unit of scientific units.
Is the erg to kilojoule conversion exact?
Yes. Both erg and kilojoule are defined by fixed standards rather than physical artifacts, so the factor of 1e-10 used above is exact to as many digits as you choose to display.
Why does this category span everything from atomic to astronomical scales?
Scientific work spans an enormous range of physical scales, from atomic distances (measured in angstroms or atomic mass units) to interstellar distances (measured in astronomical units or parsecs), so this category groups SI-derived and scale-specific units that researchers commonly need to convert between within their field.