Convert Kilowatt-hours to Megajoules
1 kilowatt-hour (kWh) equals 3.6 megajoules (MJ).
1 kWh = 3.6 MJ
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk kilowatt-hour to megajoule converter to paste a column from Excel.
How to Convert Kilowatt-hour to Megajoule
- 1 kWh = 3.6 MJ
- 1 MJ = 0.2777777778 kWh
- Example: convert 15 kWh to MJ: 15 kWh = 15 × 3.6 MJ = 54 MJ
Formula
MJ = kWh × 3.6
Derivation from SI units:
- 1 kWh = 1000 W × 3600 s = 3.6 × 10⁶ J
- 1 MJ = 10⁶ J
- 1 kWh = 3600000 J ÷ 1000000 J per MJ = 3.6 MJ
Both units are defined exactly, so the factor is exact. Kilowatt-hour definition: kilowatt-hour; Megajoule definition: megajoule.
Worked examples
- 1 kWh is exactly 3.6 MJ.
1 kWh × 3.6 = 3.6 MJ - A 75 kWh EV battery stores 270 MJ.
75 kWh × 3.6 = 270 MJ
Kilowatt-hour to Megajoule conversion table
| Kilowatt-hours (kWh) | Megajoules (MJ) |
|---|---|
| 0.1 kWh | 0.36 MJ |
| 0.5 kWh | 1.8 MJ |
| 1 kWh | 3.6 MJ |
| 2 kWh | 7.2 MJ |
| 5 kWh | 18 MJ |
| 10 kWh | 36 MJ |
| 13.5 kWh | 48.6 MJ |
| 20 kWh | 72 MJ |
| 30 kWh | 108 MJ |
| 50 kWh | 180 MJ |
| 75 kWh | 270 MJ |
| 100 kWh | 360 MJ |
| 300 kWh | 1080 MJ |
| 900 kWh | 3240 MJ |
| 1000 kWh | 3600 MJ |
| 10000 kWh | 36000 MJ |
Where it's used
Electricity in kWh is converted to megajoules to compare with fuel heating values given in MJ. 1 kWh = 3.6 MJ exactly.
Kilowatt-hour to other energy units
| Conversion | 1 kWh equals |
|---|---|
| kilowatt-hour to joule | 3600000 J |
| kilowatt-hour to kilojoule | 3600 kJ |
| kilowatt-hour to megajoule | 3.6 MJ |
| kilowatt-hour to calorie | 860420.6501 cal |
| kilowatt-hour to kilocalorie | 860.4206501 kcal |
| kilowatt-hour to watt-hour | 1000 Wh |
| kilowatt-hour to BTU | 3412.141633 BTU |
| kilowatt-hour to therm | 0.03412956341 thm |
| kilowatt-hour to electronvolt | 2.246943267 × 10²⁵ eV |
| kilowatt-hour to foot-pound | 2655223.737 ft·lbf |
| kilowatt-hour to erg | 36000000000000 erg |
Frequently asked questions
Why is 1 kWh 3.6 MJ?
One kilowatt for one hour is 1000 J/s × 3600 s = 3 600 000 J.
How many megajoules are in 1 kilowatt-hour?
1 kWh = 3.6 MJ.
How do I convert kilowatt-hours to megajoules?
Multiply the value in kWh by 3.6. For example, 15 kWh × 3.6 = 54 MJ.
Is the kWh to MJ conversion exact?
Yes. Both units are defined exactly, and 1 kWh is exactly 3.6 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, "kilowatt hour (kW·h)".
- 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 Kilowatt-hours to Megajoules. Retrieved October 17, 2026, from https://scientificconverters.com/energy/kilowatt-hours-to-megajoules/
IEEE
Scientific Converters, "Convert Kilowatt-hours to Megajoules," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/energy/kilowatt-hours-to-megajoules/