Watt to Milliwatt Converter
Convert watts to milliwatts (W to mW) instantly with this free online power converter. Enter any value in the Watt field and get the equivalent in Milliwatt immediately. This converter handles any quantity — from tiny fractions to large numbers — with full precision. No signup, no ads in the widget, and the conversion runs entirely in your browser for instant results.
The conversion factor is exact: 1 W = 1000 mW. To convert watts to milliwatts, multiply your Watt value by 1000. For example, 10 W = 10000 mW. You can also reverse the calculation: 1 mW = 0.001 W.
Quick conversion table
| Watt (W) | Milliwatt (mW) |
|---|---|
| 1 W | 1000 mW |
| 5 W | 5000 mW |
| 10 W | 10000 mW |
| 25 W | 25000 mW |
| 50 W | 50000 mW |
| 100 W | 100000 mW |
Use the swap button to reverse the direction, or choose a different unit from the dropdown menus to convert within the power category.
Formula
Watt to Milliwatt conversion: 1 W = 1000 mW milliwatts = watts × 1000 1 mW = 0.001 W watts = milliwatts × 0.001
Example
Example: Convert 10 W to mW: 10 W × 1000 = 10000 mW So, 10 W is about 10000 mW. To convert back, multiply by 0.001: 10000 mW × 0.001 = 10 W.
How to Use
- Enter the value you want to convert in the Watt field
- The result in Milliwatt appears instantly below
- Use the dropdown menus to change units if needed
- Click 'Swap Units' to reverse the conversion direction
- Copy the result or adjust the input for a new conversion
Frequently Asked Questions
How do I convert watts to milliwatts?
Enter the value in Watt (W) in the 'From' field. The equivalent in Milliwatt (mW) appears instantly in the 'To' field. The converter uses precise conversion factors and updates in real time as you type.
What is the formula to convert W to mW?
1 W = 1000 mW, so milliwatts = watts × 1000. To convert back, 1 mW = 0.001 W. The full formula and a worked example are shown on this page.
How many milliwatts are in one Watt?
1 W = 1000 mW.
Is this Watt to Milliwatt converter free?
Yes, completely free with no signup, no limits, and no ads in the converter widget. You can convert as many values as you need. The tool runs entirely in your browser, so your data never leaves your device.
Can I convert milliwatts back to watts?
Yes. Click the 'Swap Units' button to reverse the direction. You can also use the dropdown menus to select any other power unit for either field.
How accurate is the W to mW conversion?
The converter uses high-precision conversion factors (up to 8 decimal places). Results are displayed with up to 6 decimal places, with trailing zeros removed for readability. For scientific or engineering work, always verify with official standards.