Kilojoules (kJ) to Ergs Converter
Enter a value to instantly convert between energy units.
1 Kilojoule = 1.0000e+10 Erg
Key Formulas
Kilocalorie → Kilojoule
kJ = kcal × 4.184Kilojoule → Kilocalorie
kcal = kJ × 0.239006Kilowatt-Hour → Joule
J = kWh × 3600000Joule → Kilowatt-Hour
kWh = J × 2.77778e-7Formula
erg = kJ × 1.0e+10Kilojoules are the modern SI energy unit, while ergs are the CGS (centimeter–gram–second) unit. You need this conversion when reading older physics papers, comparing experimental data across measurement systems, or working with spectroscopy equipment calibrated in ergs. The conversion factor (10^10) reflects the ratio of joule to erg definitions in their respective systems.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A physicist converting 1 kJ of energy from a modern apparatus into ergs for a legacy spectroscopy calculation — 10 billion ergs, the unit used in pre-1960s physics labs.
1 kJ = 10000000000 erg
A researcher measuring 10 joules of photon energy (0.01 kJ) from a laser, reported as 100 million ergs in published CGS-based data.
0.01 kJ = 100000000 erg
An astrophysicist studying supernova light curves, converting 5 kJ theoretical energy to 50 billion ergs for comparison with historical erg-based observations.
5 kJ = 50000000000 erg
A materials scientist calibrating an older energy analyzer, expressing 100 joules (0.1 kJ) as 1 billion ergs to match legacy instrument specifications.
0.1 kJ = 1000000000 erg