Convert Ergs to Megajoules
1 erg equals 1 × 10⁻¹³ megajoules (MJ).
1 erg = 1e-13 MJ
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk erg to megajoule converter to paste a column from Excel.
How to Convert Erg to Megajoule
- 1 erg = 1 × 10⁻¹³ MJ
- 1 MJ = 10000000000000 erg
- Example: convert 15 erg to MJ: 15 erg = 15 × 1 × 10⁻¹³ MJ = 1.5 × 10⁻¹² MJ
Formula
MJ = erg ÷ 10000000000000
Derivation from SI units:
- 1 erg = 1 dyn·cm = 10⁻⁷ J
- 1 MJ = 10⁶ J
- 1 erg = 1 × 10⁻⁷ J ÷ 1000000 J per MJ = 1 × 10⁻¹³ MJ
Both units are defined exactly, so the factor is exact. Erg definition: erg; Megajoule definition: megajoule.
Worked examples
- A reading of 1000 erg converts to 1 × 10⁻¹⁰ MJ.
1000 erg × 1 × 10⁻¹³ = 1 × 10⁻¹⁰ MJ - A value of 1e6 erg is 1 × 10⁻⁷ MJ.
1e6 erg × 1 × 10⁻¹³ = 1 × 10⁻⁷ MJ
Erg to Megajoule conversion table
| Ergs (erg) | Megajoules (MJ) |
|---|---|
| 1 erg | 1 × 10⁻¹³ MJ |
| 10 erg | 1 × 10⁻¹² MJ |
| 100 erg | 1 × 10⁻¹¹ MJ |
| 1000 erg | 1 × 10⁻¹⁰ MJ |
| 10000 erg | 1 × 10⁻⁹ MJ |
| 1e5 erg | 1 × 10⁻⁸ MJ |
| 1e6 erg | 1 × 10⁻⁷ MJ |
| 1e7 erg | 0.000001 MJ |
| 1e10 erg | 0.001 MJ |
| 3.828e33 erg | 3.828 × 10²⁰ MJ |
Where it's used
Ergs are used for astrophysics (luminosities in erg/s), while megajoules appear in fuel heating values (natural gas ≈ 38 MJ/m³, diesel ≈ 45 MJ/kg). Both measure energy, work and heat, so the conversion is a fixed factor.
Erg to other energy units
| Conversion | 1 erg equals |
|---|---|
| erg to joule | 1 × 10⁻⁷ J |
| erg to kilojoule | 1 × 10⁻¹⁰ kJ |
| erg to megajoule | 1 × 10⁻¹³ MJ |
| erg to calorie | 2.390057361 × 10⁻⁸ cal |
| erg to kilocalorie | 2.390057361 × 10⁻¹¹ kcal |
| erg to watt-hour | 2.777777778 × 10⁻¹¹ Wh |
| erg to kilowatt-hour | 2.777777778 × 10⁻¹⁴ kWh |
| erg to BTU | 9.478171203 × 10⁻¹¹ BTU |
| erg to therm | 9.48043428 × 10⁻¹⁶ thm |
| erg to electronvolt | 624150907400 eV |
| erg to foot-pound | 7.375621493 × 10⁻⁸ ft·lbf |
Frequently asked questions
How many megajoules are in 1 erg?
1 erg = 1 × 10⁻¹³ MJ.
How do I convert ergs to megajoules?
Multiply the value in erg by 1 × 10⁻¹³, or divide it by 10000000000000. For example, 15 erg × 1 × 10⁻¹³ = 1.5 × 10⁻¹² MJ.
Is the erg to MJ conversion exact?
Yes. Both units are defined exactly, and 1 erg is exactly 1 × 10⁻¹³ MJ.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "erg (erg)".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Ergs to Megajoules. Retrieved October 17, 2026, from https://scientificconverters.com/energy/ergs-to-megajoules/
IEEE
Scientific Converters, "Convert Ergs to Megajoules," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/energy/ergs-to-megajoules/