Unit Converter
Convert From Kilowatt-Hours to Megajoules and Vice Versa
kWh ↔ MJ
Type in either kilowatt-hours or megajoules — it’ll convert to the other automatically!
⚡ What is a Kilowatt-hour (kWh)?
A kilowatt-hour is a unit of **energy** used to measure **electrical consumption**. It represents the energy used when a device with 1 kilowatt power rating runs for 1 hour. It’s the standard unit on **electricity bills**. 1 kWh = 3.6 Megajoules (MJ).
🔋 What is a Megajoule (MJ)?
A megajoule is a **metric unit of energy** equal to 1,000,000 joules. It is used in **engineering**, **fuels**, **mechanical systems**, and increasingly in **renewable energy systems**. 1 MJ ≈ 0.2778 kWh.
🧠 Quick Comparison
| Unit | Equivalent | Used In |
|---|---|---|
| 1 kWh | 3.6 MJ | Electricity bills, household energy |
| 1 MJ | 0.2778 kWh | Fuel energy, mechanical systems |
🧮 How to Convert
Kilowatt-hours to Megajoules:
MJ = kWh × 3.6
Megajoules to Kilowatt-hours:
kWh = MJ ÷ 3.6
🧪 Example:
2 kWh × 3.6 = 7.2 MJ
💡 Quick Tip
1 MJ is roughly the energy used to boil a full kettle. Multiply your electricity bill units (kWh) by 3.6 to get equivalent energy in MJ.
🎉 Did You Know?
A single slice of toast takes about 0.04 kWh — or **0.144 MJ**. Multiply that by a million homes and energy use really adds up!
🌍 Real-World Energy Examples
- 1 kWh – One hour of a 1000-watt space heater
- 3.6 MJ – Energy of 1 kWh in mechanical terms
- 36 MJ – Energy in 1 liter of petrol/gasoline
- 60 MJ – Daily energy needs of a typical person (food)
📊 Kilowatt-hours to Megajoules Conversion Chart
| kWh | Megajoules (MJ) |
|---|---|
| 0.5 | 1.80 |
| 1 | 3.60 |
| 2 | 7.20 |
| 5 | 18.00 |
| 10 | 36.00 |
| 50 | 180.00 |
📜 Timeline: Energy Unit Evolution
- 1800s: Joule defined based on mechanical work
- 1900s: Watt-hour and kilowatt-hour adopted for electrical systems
- Today: Both kWh and MJ are used across different industries and regions
🌐 When to Use kWh vs MJ
- 🔌 kWh: Electric meters, utilities, home appliances
- ⛽ MJ: Fuel energy content, engines, scientific research
- 🧮 Quick Tip: Multiply kWh × 3.6 to convert to MJ
🎯 Interactive Converter
2 kWh = 7.20 MJ