Kilowatt is 1000 watt units.
Kilowatts to Milliwatts Converter — kW to mW
Convert Kilowatt (kW) to Milliwatt (mW) using the exact conversion factor (1 kilowatt = 1,000,000 milliwatt). See the formula, worked examples, conversion table, history, and common uses.
Kilowatts to Milliwatts converter
Converter
Power Converter
Convert watts, horsepower, refrigeration tons, BTU per hour, and engineering power units.
Context values
Some unit families need one extra value for a physically accurate result.
Milliwatt is 0.001 watt units.
Result = input x 1000 / 0.001.
Power uses the watt as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Kilowatts to Milliwatts
Kilowatt and Milliwatt both describe power output, and the conversion is a routine part of comparing an engine or motor's spec sheet across countries that use different power units. Kilowatt is most often used for electric vehicle motor power ratings (alongside horsepower).
Formula
milliwatts = kilowatts × 1000000
This factor comes from each unit's defined relationship to the category's base unit: 1 kilowatt equals 1000 base units, and 1 milliwatt equals 0.001 base units, so dividing one by the other gives the direct kilowatt-to-milliwatt factor of 1000000.
Simple example
1 kW × 1000000 = 1,000,000 mW
1 kilowatt = 1,000,000 milliwatts.
Real-world example
100 kW × 1000000 = 100,000,000 mW
100 kilowatts = 100,000,000 milliwatts.
Conversion table
| Kilowatt (kW) | Milliwatt (mW) |
|---|---|
| 1 kW | 1,000,000 mW |
| 10 kW | 10,000,000 mW |
| 100 kW | 100,000,000 mW |
| 500 kW | 500,000,000 mW |
| 1,000 kW | 1,000,000,000 mW |
| 5,000 kW | 5,000,000,000 mW |
Reverse conversion: Milliwatt to Kilowatt
1 mW × 0.000001 = 0.000001 kW
1 milliwatt = 0.000001 kilowatts.
kilowatts = milliwatts × 0.000001
For a page dedicated to this direction, see Milliwatt to Kilowatt.
Understanding the Kilowatt
Kilowatt (kW) measures power. A kilowatt is 1,000 watts. It is classified as a SI derived (metric prefix) unit.
Where it's used: Standard power unit worldwide for larger appliances, vehicles, and electrical systems
Uses of the Kilowatt today
- Electric vehicle motor power ratings (alongside horsepower)
- Household electrical system and generator capacity
- Industrial motor and equipment power ratings
History of the Kilowatt
The kilowatt follows directly from the watt via the standard SI 'kilo-' prefix, becoming especially prominent with the growth of electrical power generation and distribution in the late 19th and 20th centuries.
Historical origin. Kilowatt was not the invention of a single named person; it developed through the process described above.
Understanding the Milliwatt (mW)
Milliwatt is 0.001 watt units.
Kilowatt — sources
- BIPM SI Brochure — SI prefixes — Defines 'kilo-' as the prefix for 10³.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many milliwatts are in 1 kilowatt?
1 kilowatt equals 1,000,000 milliwatts, using the exact defined conversion factor rather than an estimate.
How do I convert kilowatt to milliwatt?
Multiply the kilowatt value by 1000000. The converter above does this instantly to whatever precision you set.
How do I convert milliwatt back to kilowatt?
Use the reverse factor: 1 milliwatt equals 0.000001 kilowatts. You can also use the swap control in the converter above to flip the direction instantly.
What is a kilowatt?
Kilowatt (kW) measures power. A kilowatt is 1,000 watts. It is classified as a SI derived (metric prefix) unit.
What is a milliwatt?
Milliwatt (mW) is a unit of power.
Is the kilowatt to milliwatt conversion exact?
Yes. Both kilowatt and milliwatt are defined by fixed standards rather than physical artifacts, so the factor of 1000000 used above is exact to as many digits as you choose to display.
Where is the kilowatt still used today?
Standard power unit worldwide for larger appliances, vehicles, and electrical systems