Convert Watt to Kilowatt (W → kW)

Converting watts to kilowatts 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 watts

   Start with the number of watts (W) you want to convert.
2. 2
   Multiply by 0.001

   The conversion factor from W to kW is 0.001. Multiply your value by this number.
3. 3
   Read the result in kilowatts

   The result is your value in kilowatts (kW).

Multiply the value in watts by 0.001. For the reverse direction, multiply by 1,000.

• ✓1 W = 1 J/s = 1 V × 1 A (for DC).
• ✓LED lighting: 10× more efficient than incandescent.
• ✓For home appliances, rating × hours used = kWh.

• ✗Confusing watts (power) with joules (energy).
• ✗Assuming "100 W bulb" for LED — old incandescent rating.
• ✗Mixing W with V or A — different quantities.

What is the Watt?

The watt is the SI unit of power, equal to one joule per second (1 W = 1 J/s). Named after Scottish engineer James Watt (1736–1819), whose improvements to the steam engine sparked the Industrial Revolution, the watt unifies mechanical, electrical, and thermal power. A typical LED bulb consumes 8–12 W to produce as much light as a 60-W incandescent bulb. Human resting metabolism is about 80–100 W of heat output, while peak athletic performance reaches 400–1,500 W (briefly). The watt is fundamental in electrical engineering: P = V × I (power = voltage × current). It relates to the kilowatt (1 kW = 1,000 W), the megawatt (1 MW = 10⁶ W), horsepower (1 hp ≈ 745.7 W), and the BTU per hour (1 W ≈ 3.412 BTU/h). Light bulb and appliance ratings, electric motor outputs, and audio amplifier specifications all use the watt as the base unit.

• Light-bulb and appliance ratings
• Scientific and engineering power specs
• Radio and electronics power

What is the Kilowatt?

The kilowatt equals 1,000 watts and is the standard power rating for European cars, household appliances, and small industrial motors. European car engines are rated in kW (a typical economy car has 70–110 kW, a sports car 200–500 kW), even though horsepower is often quoted alongside for marketing. Major household appliances range from 1–3 kW (electric kettle, microwave) to 5–10 kW (electric oven, central air conditioning). Solar panel arrays for homes are sized in kW (typical residential system: 5–10 kW). Electric motors in industry are commonly rated 1 to 500 kW. The kilowatt relates to the watt (1,000 W = 1 kW), the megawatt (1,000 kW = 1 MW), horsepower (1 kW ≈ 1.341 hp), the BTU per hour (1 kW ≈ 3,412 BTU/h), and the kWh of energy when multiplied by hours.

• Car and motorcycle engine ratings (Europe)
• Home electrical service sizing
• HVAC and heating-pump capacity