The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
Watts to Milliwatts
Convert Watt (W) to Milliwatt (mW) instantly with an exact formula, conversion table, and FAQ.
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Convert watts (W) to milliwatts (mW) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A Milliwatt (mW) equals 1/1,000 watt(s), a scaled unit of electrical power used for milli-scale electrical work.
mW = W × 1000
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Formula
mW = W × 1000
W = mW × 0.001
Conversion table
| 1 W | 1000 mW |
| 5 W | 5000 mW |
| 10 W | 10000 mW |
| 20 W | 20000 mW |
| 50 W | 50000 mW |
| 100 W | 100000 mW |
| 500 W | 500000 mW |
| 1000 W | 1.000000e+06 mW |
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How the formula works
Both watt and milliwatt measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in watts by 1000 to get milliwatts. To reverse the conversion, multiply a milliwatt value by 0.001 to get back to watts.
Frequently asked questions
What is Watt (W)?
The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
What is Milliwatt (mW)?
A Milliwatt (mW) equals 1/1,000 watt(s), a scaled unit of electrical power used for milli-scale electrical work.
How do I convert watts to milliwatts?
Multiply the watt value by 1000 to get the equivalent in milliwatts. For example, 5 W × 1000 = 5000 mW.
Is this conversion exact?
Yes. Both units use fixed, defined scale factors, so the factor 1000 is an exact, non-rounded value.
Can I convert milliwatts back to watts?
Yes. Divide the milliwatt value by 1000, or multiply it by 0.001, to get watts.
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About converting watts to milliwatts
The watt (W) is the SI unit of power, equal to one joule of energy transferred per second. A Milliwatt (mW) equals 1/1,000 watt(s), a scaled unit of electrical power used for milli-scale electrical work.
Use this calculator to move between watts and milliwatts accurately for homework, engineering, billing, or everyday electricity calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.