Watt to Milliwatt Converter
Convert Watt (W) to Milliwatt (mW) instantly. 1 W = 1,000 mW.
Power Converter
22 units available
1 W = 1,000 mW
Formula:
mW = W × 1,000With your value: 1 W = 1,000 mW
How big is that?
Everyday references on a logarithmic scale, all expressed in watt so you can sanity-check the result.
Other Watt to Milliwatt conversions
Watt to Milliwatt Conversion Table
| Watt (W) | Milliwatt (mW) |
|---|---|
| 0.5 | 500 |
| 1 | 1,000 |
| 2 | 2,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 15 | 15,000 |
| 20 | 20,000 |
| 25 | 25,000 |
| 50 | 50,000 |
| 100 | 100,000 |
| 250 | 250,000 |
| 500 | 500,000 |
| 1000 | 1,000,000 |
Milliwatt to Watt Conversion Table
| Milliwatt (mW) | Watt (W) |
|---|---|
| 0.5 | 0.0005 |
| 1 | 0.001 |
| 2 | 0.002 |
| 5 | 0.005 |
| 10 | 0.01 |
| 15 | 0.015 |
| 20 | 0.02 |
| 25 | 0.025 |
| 50 | 0.05 |
| 100 | 0.1 |
| 250 | 0.25 |
| 500 | 0.5 |
| 1000 | 1 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
Watt (W)
Power
Derived from the watt (1 W = 1 J/s).
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
Milliwatt (mW)
Power
Derived from the watt (1 W = 1 J/s).
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
How to Convert Watt to Milliwatt
To convert from Watt (W) to Milliwatt (mW), multiply the value by 1,000.
Formula: mW = W × 1,000
Reverse: W = mW × 0.001
Step-by-Step Example
- Start with your value in Watt. For example: 5 W
- Multiply by the conversion factor: 5 x 1,000
- The result is: 5,000 mW
About Watt
The watt (W) is a unit of power. One watt equals 1 watt. UnitConvertLab converts it against every other power unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
Common uses: power calculations, engineering and science, education.
About Milliwatt
The milliwatt (mW) is a unit of power. One milliwatt equals 0.001 watts. UnitConvertLab converts it against every other power unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
Common uses: power calculations, engineering and science, education.
Frequently Asked Questions
How many Milliwatt are in 1 Watt?
There are exactly 1,000 Milliwatt in 1 Watt. This means the conversion factor from Watt to Milliwatt is 1,000.
What is the formula to convert Watt to Milliwatt?
The formula to convert Watt to Milliwatt is: mW = W × 1,000. For example, to convert 10 Watt to Milliwatt, you would multiply 10 by 1,000.
What is a Watt?
The watt (W) is a unit of power. One watt equals 1 watt. UnitConvertLab converts it against every other power unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
What is a Milliwatt?
The milliwatt (mW) is a unit of power. One milliwatt equals 0.001 watts. UnitConvertLab converts it against every other power unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
What are the common uses of Watt?
The Watt is commonly used in power calculations, engineering and science, education.
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Cite this page
UnitConvertLab. (2026). Watt to Milliwatt converter. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/watt-to-milliwatt