Megajoules to Kilowatt-hours (MJ to kWh)

Formula

1 MJ = 0.277778 kWh

kilowatt-hours = megajoules × 0.2777777778 — reverse: megajoules = kilowatt-hours × 3.6

The factor is derived from the SI definitions of both units (base unit: J) as listed in NIST SP 811; results on this page are shown to 6 significant figures, the API returns up to 12.

Worked examples

• 5 MJ = 1.38889 kWh
• 12.5 MJ = 3.47222 kWh
• 100 MJ = 27.7778 kWh

Megajoules to kilowatt-hours conversion table

FAQ

How many kilowatt-hours are in one megajoule?

1 MJ = 0.277778 kWh. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

What is the formula to convert megajoules to kilowatt-hours?

Multiply the value in megajoules by 0.2777777778: kilowatt-hours = megajoules × 0.2777777778. For example, 5 MJ = 1.38889 kWh.

How do I convert kilowatt-hours back to megajoules?

Multiply by the inverse factor 3.6 (megajoules = kilowatt-hours × 3.6), or use the kilowatt-hours-to-megajoules page.

Related conversions

• Kilowatt-hours to megajoules (reverse)
• Energy Converter — all energy units in one tool
• Kilocalories (food calories) to Kilojoules
• Kilojoules to Kilocalories (food calories)
• Joules to Calories (small, thermochemical)
• Calories (small, thermochemical) to Joules
• Kilowatt-hours to BTU
• BTU to Kilowatt-hours
• BTU to Joules
• Joules to BTU

Machine access

• API: GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=MJ&to_unit=kWh
• MCP: server https://tttkmbb.com/mcp, tool convert_units with {"value":5,"from_unit":"MJ","to_unit":"kWh"}
• Markdown: https://tttkmbb.com/conversion/mj-to-kwh.md · JSON: https://tttkmbb.com/conversion/mj-to-kwh.json (add ?value= for a result) · Units: /api/v1/units?quantity=energy
• OpenAPI operationId: convert_units. Freshness: static. Authentication: none.

Sources

• NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors (standard)
• BIPM – The International System of Units (SI Brochure, 9th edition) (standard)
• Wikipedia – Conversion of units (reference)