Convert Kilowatt-Hour to Watt-Hour (kWh → Wh)

Converting kilowatt-hours to watt-hours is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in kilowatt-hours

   Start with the number of kilowatt-hours (kWh) you want to convert.
2. 2
   Multiply by 1,000

   The conversion factor from kWh to Wh is 1,000. Multiply your value by this number.
3. 3
   Read the result in watt-hours

   The result is your value in watt-hours (Wh).

Multiply the value in kilowatt-hours by 1,000. For the reverse direction, multiply by 0.001.

• ✓1 kWh = 3.6 MJ = 3,600,000 J.
• ✓Multiply device power (kW) × time (h) = energy (kWh).
• ✓EV "range anxiety" translates to knowing kWh available.

• ✗Confusing kWh (energy) with kW (power).
• ✗Calculating electric costs by power ignoring duration.
• ✗Using "kWh/h" — redundant; it's just kW.

What is the Kilowatt-Hour?

The kilowatt-hour equals 1,000 watt-hours (3.6 megajoules) and is the universal billing unit for residential electricity consumption around the world. A typical US household uses about 800–1,000 kWh per month; a refrigerator consumes 1–2 kWh per day, an LED bulb at 10 W for 10 hours uses 0.1 kWh, and a Tesla Model 3 has a 75 kWh battery (about 250–350 miles of range). Electric utility rates are quoted in cents per kWh — typical US residential rates are 11–25 ¢/kWh, while industrial rates are lower. The kilowatt-hour is essential in renewable-energy planning: solar panel output, wind farm production, and grid-scale storage are all rated in kWh or MWh (megawatt-hours). It relates to the watt-hour (1,000 Wh = 1 kWh), the joule (1 kWh = 3.6 MJ), the BTU (1 kWh ≈ 3,412 BTU), and the megawatt-hour (1,000 kWh = 1 MWh).

• Electricity billing globally
• EV battery capacity specifications
• Home solar and battery storage

What is the Watt-Hour?

The watt-hour equals exactly 3,600 joules and is the standard unit for small-battery capacity, household electrical energy, and renewable-energy storage. A smartphone battery stores roughly 12–15 Wh, a laptop battery 50–100 Wh, and an electric car battery 60,000–100,000 Wh (60–100 kWh). The watt-hour represents the energy delivered by a 1-watt device running for 1 hour. It is the natural unit for connecting power (watts) to time, which is why electric utilities bill in kilowatt-hours. The watt-hour relates to the joule (3,600 J = 1 Wh), the kilowatt-hour (1,000 Wh = 1 kWh), and the BTU (1 Wh ≈ 3.412 BTU). Battery capacity, solar panel output (Wh per day), and energy storage system specifications all rely on the watt-hour as the base small-energy unit.

• Laptop and phone battery capacity
• Portable power banks and UPS
• Home solar panel daily output