Kilowatt-hours: conversions & definition
One kilowatt-hour equals 1,000 watt-hours or 3.6 megajoules. To estimate a bill, multiply kWh by the tariff per kWh and add any applicable fixed charges separately.
Choose the unit you need
Each row converts one kWh. Open a converter to enter any value and see its formula, worked example and reference table. Results below are rounded to 10 significant digits.
| Convert to | Equivalent value | Calculator |
|---|---|---|
| Joules (J) | ≈ 3,600,000 | Convert kWh to J |
| Kilojoules (kJ) | ≈ 3,600 | Convert kWh to kJ |
| Megajoules (MJ) | ≈ 3.6 | Convert kWh to MJ |
| Watt-hours (Wh) | ≈ 1,000 | Convert kWh to Wh |
| Kilocalories (kcal th) | ≈ 860.4206501 | Convert kWh to kcal th |
Keep the quantity consistent
Choose units that represent the same quantity and preserve the measurement conditions. A scale conversion changes the number and unit together; it does not change the physical amount or improve the accuracy of your measurement.
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