Watts to milliwatts
Type a value in watts to see it in milliwatts straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the watts box.
- Read the result in milliwatts as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
mW = W × 1,000
Multiply the value in watts by 1,000 to get milliwatts.
Example
To convert 25 W to milliwatts: 25 × 1,000 = 25,000 mW.
Conversion table
| Watts (W) | Milliwatts (mW) |
|---|---|
| 1 | 1,000 |
| 2 | 2,000 |
| 3 | 3,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 20 | 20,000 |
| 25 | 25,000 |
| 50 | 50,000 |
| 100 | 100,000 |
| 250 | 250,000 |
| 500 | 500,000 |
| 1,000 | 1,000,000 |
About the units
- Watt
- The SI unit of power, equal to one joule per second.
- Milliwatt
- A milliwatt is one thousandth of a watt, used for laser pointers, radio signals and small electronics.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many milliwatts are in one watt?
1 W = 1,000 mW exactly.
How do I convert watts to milliwatts?
Use mW = W × 1,000. For example, 25 W = 25,000 mW.
How many watts are in one milliwatt?
1 mW = 0.001 W.
What is the difference between mechanical and metric horsepower?
Mechanical horsepower is about 745.7 watts and is used in the US, while metric horsepower (PS) is 735.5 watts and is used in Europe and Japan. The same engine therefore shows a PS figure about 1.4% higher.
How many kilowatts is one ton of refrigeration?
One ton of refrigeration is 12000 BTU per hour, about 3.517 kW of cooling capacity. That is cooling output, not electricity use; the unit draws less power depending on its efficiency.