Ergs to Kilojoules (kJ) Converter
Enter a value to instantly convert between energy units.
1 Erg = 1.0000e-10 Kilojoule
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
kJ = erg × 1.000000e-10One erg equals 10⁻¹⁰ kilojoules (0.1 nanojoules). The erg is the CGS energy unit used in astrophysics, cosmology, and older scientific literature. Kilojoules are the modern SI standard. Converting ergs to kJ is essential when publishing astrophysical results (supernova energies, stellar output) in international journals requiring SI units. See also ergs to BTU.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A typical supernova releases ~10⁵¹ erg — 10⁴¹ kJ or 100 million trillion trillion kilojoules.
1e+51 erg = 1e+41 kJ
A gamma-ray burst: ~10⁵⁰ erg = 10⁴⁰ kJ. An astrophysicist converts this for an international energy conference.
1e+50 erg = 1e+40 kJ
A solar flare releases 10¹⁰ erg — exactly 1 kJ — showing the huge range of erg use across scales.
10000000000 erg = 1 kJ
A chemistry reaction: 10⁷ erg = 0.001 kJ = 1 J. Lab measurement converted to SI units for the report.
10000000 erg = 0.001 kJ