Kilowatt Hours to Joules
A kilowatt-hour is 1,000 watt-hours, the unit electricity companies use to bill household power usage. The joule is the SI unit of energy, defined as the work done by one newton over one meter. 1 kWh equals 3,600,000 J, so converting between them is a matter of multiplying by that fixed factor — type any value into the converter below and both sides update instantly as you type.
Both units belong to energy, measured here against energy's base unit (J) — every other energy unit on this site converts through that same reference point, which is why the table below can also be read as a quick cross-check against nearby values.
Formula
J = kWh × 3,600,000
kWh = J × 2.77778e-7
Worked example: 5 kWh × 3,600,000 = 18,000,000 J.
Conversion table
| Kilowatt-hour (kWh) | Joule (J) |
|---|---|
| 1 kWh | 3,600,000 J |
| 2 kWh | 7,200,000 J |
| 3 kWh | 10,800,000 J |
| 5 kWh | 18,000,000 J |
| 10 kWh | 36,000,000 J |
| 20 kWh | 72,000,000 J |
| 25 kWh | 90,000,000 J |
| 50 kWh | 180,000,000 J |
| 100 kWh | 360,000,000 J |
| 250 kWh | 900,000,000 J |
| 500 kWh | 1,800,000,000 J |
| 1,000 kWh | 3,600,000,000 J |
Frequently asked
- How many Joules in a kilowatt-hour?
- 1 kWh equals 3,600,000 J.
- How do I convert Kilowatt-hours to Joules?
- Multiply the value in kWh by 3,600,000 to get J. The converter above does this instantly as you type.
- Is the conversion exact?
- Yes — Kilowatt-hour and Joule are both defined by a fixed conversion factor to energy's base unit (J), so the result shown is exact to the precision displayed, not an approximation.