Kilowatts to Milliwatts (kW to mW)

1 kilowatt equals 1,000,000 milliwatts exactly.

1 kilowatt = 1,000,000 milliwatts

How to convert kilowatts to milliwatts

To convert kilowatts to milliwatts, multiply the number of kilowatts by 1,000,000. This factor is exact. To go the other way, multiply milliwatts by 0.000001.

milliwatts = kilowatts × 1,000,000

Example: 10 kilowatts = 10,000,000 milliwatts.

Several different horsepower units exist. This site lists mechanical (745.7 W), metric (735.5 W) and electrical (746 W) horsepower separately.

About these units

Kilowatt (kW)

Metric (SI)Current unit

1,000 watts. Used for the power of motors, cars and household appliances.

A kilowatt is simply the watt with the SI prefix kilo, meaning a thousand, attached. The watt was adopted into the SI in 1960 and is small next to machinery, since an incandescent night light uses about 4 W, so the thousand-watt multiple suits engines, electric motors, tools and heaters. For readers used to older units, one kilowatt is roughly 1.34 horsepower.

Small electric heaters with a single element can use about 1 kW, and a domestic electric kettle or microwave oven draws a similar amount. The average household in the United States uses about 1 kW of electric power over time. On a clear midday near the equator, a square meter of Earth's surface receives about 1 kW of sunlight. Do not confuse the kilowatt with the kilowatt-hour on an electricity bill: the first is a rate, the second is the energy used by running one kilowatt for an hour, which equals 3,600,000 watt-seconds.

1 kilowatt = 1,000 watts (exactly).

Sources: Wikipedia: Kilowatt; Wikipedia: Orders of magnitude (power); BIPM: SI prefixes

Milliwatt (mW)

Metric (SI)Current unit

One thousandth of a watt. Used for lasers and small electronics.

A thousandth of a watt sounds negligible, but it is the working scale for a great deal of light and signal technology. A common laser pointer emits about five milliwatts of light, and a hearing aid draws less than one. The watt is named for James Watt, with the name proposed by C. William Siemens in 1882 and the unit placed in the SI by the General Conference on Weights and Measures in 1960, and the milliwatt simply applies the standard milli prefix to it.

Radio and audio engineers use the milliwatt as a zero point. A level in dBm is a power measured in decibels relative to one milliwatt, so 0 dBm is exactly 1 mW and each 10 dB step multiplies or divides the power by ten. One milliwatt is 0.001 watt, 1,000 microwatts, and 10,000 ergs per second in the older CGS system, since one watt equals 10 million ergs per second.

1 milliwatt = 0.001 watts (exactly).

Sources: Wikipedia: Watt

Related conversions

See all power units.