Milliwatt (mW)
The milliwatt (mW) is one thousandth of a watt.
Symbol: mW
Quantity: power (energy per unit time)
SI relation: 1 mW = 0.001 W (exact)
Derivation: 1 mW = 10⁻³ W
Exact: yes, by definition
Typical uses
- Laser pointer and diode output
- RF and radio transmit power (dBm references 1 mW)
- Low-power sensors and electronics
Convert milliwatts to other units
| Conversion | 1 mW equals | Reverse |
|---|---|---|
| milliwatt to watt | 0.001 W | watt to milliwatt |
| milliwatt to kilowatt | 0.000001 kW | kilowatt to milliwatt |
| milliwatt to horsepower | 0.00000134102209 hp | horsepower to milliwatt |
| milliwatt to BTU per hour | 0.003412141633 BTU/h | BTU per hour to milliwatt |
| milliwatt to refrigeration ton | 2.843451361 × 10⁻⁷ TR | refrigeration ton to milliwatt |
| milliwatt to megawatt | 1 × 10⁻⁹ MW | megawatt to milliwatt |
| milliwatt to metric horsepower | 0.000001359621617 PS | metric horsepower to milliwatt |
| milliwatt to kilocalorie per hour | 0.0008598452279 kcal/h | kilocalorie per hour to milliwatt |
| milliwatt to foot-pound per second | 0.0007375621493 ft·lbf/s | foot-pound per second to milliwatt |
Open the Power Converter to convert any value between all units.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Milliwatt (mW). Retrieved October 17, 2026, from https://scientificconverters.com/units/milliwatt/
IEEE
Scientific Converters, "Milliwatt (mW)," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/units/milliwatt/