Kilowatts to Milliwatts Converter
Enter the power in kilowatts below to convert it to milliwatts.
Convert Kilowatts to Milliwatts
Enter a value in kilowatts (kW) to convert to milliwatts (mW).
Kilowatt to Milliwatt Conversion Table
Table showing various kilowatt measurements converted to milliwatts. Click any preset value or arrow to load it into the converter.
How to Convert Kilowatts to Milliwatts
To convert kilowatts to milliwatts, multiply the power by the following conversion ratio: 1,000,000 milliwatts/kilowatt.
Since one kilowatt is equal to 1,000,000 milliwatts, you can use this simple formula to convert:
The power in milliwatts is equal to the power in kilowatts multiplied by 1,000,000.
For example, here's how to convert 5 kilowatts to milliwatts using the formula above.
How Many Milliwatts Are in a Kilowatt?
There are 1,000,000 milliwatts in a kilowatt, which is why we use this value in the formula above.
Our kilowatt to milliwatt calculator automatically converts your power measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
Kilowatts and milliwatts are both units used to measure power. Keep reading to learn more about each unit.
What Is a Kilowatt?
A kilowatt is a unit of power equal to 1,000 watts (W), the base unit for power. Equal to 1,000 Watts (1 kJ/s). [1]
The kilowatt is classified as a metric and SI-compatible unit of power. Kilowatts can be abbreviated as kW; for example, 1 kilowatt can be written as 1 kW.
In the metric system, "kilo" is the standard SI prefix for thousands, or 10³. This makes the kilowatt (kW) a convenient decimal multiple of the watt (W).
In practice, kilowatts (kW) are widely used across large-scale industrial, bulk, and macro-level power specifications within SI metric workflows, engineering documentation, and technical data sheets.
What Is a Milliwatt?
A milliwatt is a unit of power equal to 1/1,000 of a watt (0.001 W). One-thousandth of a Watt. [2]
The milliwatt is classified as a metric and SI-compatible unit of power. Milliwatts can be abbreviated as mW; for example, 1 milliwatt can be written as 1 mW.
In the metric system, "milli" is the standard SI prefix for thousandths, or 10⁻³. This makes the milliwatt (mW) a convenient decimal multiple of the watt (W).
In practice, milliwatts (mW) are widely used across fine-tolerance laboratory, analytical, and micro-scale power measurements within SI metric workflows, engineering documentation, and technical data sheets.
When converting power between kilowatts (kW) and milliwatts (mW), keep full floating-point precision (1 kW = 1,000,000 mW; 1 mW = 0.000001 kW) during intermediate calculations and round only the final milliwatt figure to match your instrument tolerance.
More Kilowatt & Milliwatt Conversions
Need to calculate in the opposite direction? Use our milliwatts to kilowatts calculator to switch your starting unit immediately. You can also explore related tools such as converting milliwatts to kilowatts, converting kilowatts to horsepower (hp), or converting kilowatts to watts.
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Frequently Asked Questions
References
- [1]NIST SP 811 StandardNIST SP 811 (NIST SP 811 App. B.9 (Power & Radiant Flux))·Power Metrology Standard — Kilowatts (kW) to Milliwatts (mW)
- [2]NIST CUU SpecificationNIST CUU (Derived SI Unit: Watt (W))·Unit Specifications: Kilowatt (kW) & Milliwatt (mW)
- [3]BIPM ReferenceBIPM (SI Brochure (9th Ed.) — Power)·Conversion Factors & Mathematical Basis (kW to mW)