In electronics and communication systems, power is often expressed in milliwatts for small devices. But when dealing with ultra-low power levels, such as sensors, medical implants, or precision circuits, it’s more practical to use microwatts.
This guide explains how to convert milliwatts to microwatts with clear formulas, tables, and examples.
Definitions of Watt, Milliwatt, and Microwatt
Let’s get started by understanding the key definitions of Watt (W), Milliwatt (mW), and Microwatt (µW). Understanding these terms will allow you to perform conversions confidently.
What is Watt?
Watt (W) is the SI derived unit of power, named after James Watt, the Scottish engineer who improved the steam engine. It measures the rate of energy transfer per unit time.[1]
Mathematically 1 W = 1 j/s:
Where:
j = jouleunit of energys = secondunit of time
According to SI prefixes[2], which are based on powers of 10, a watt (1 W) is equivalent to one thousand milliwatts (103 mW or 1,000 mW) or one million microwatts (1,000,000 µF).
It is widely used to quantify electrical, mechanical, and thermal power in everyday applications such as light bulbs, appliances, and motors.
What is a Milliwatt (mW)?
A milliwatt (mW) is a unit of power in the SI system equal to one thousandth (1/1,000) of a watt (0.001 W).
Milliwatts are commonly used to measure small power levels in electronics and communication systems. Devices such as laser pointers, wireless transmitters, hearing aids, and portable audio equipment often operate in the milliwatt range, making this unit ideal for expressing precise, low-power outputs.
What is a Microwatt (µW)?
A microwatt (µW) is a unit of power in the International System of Units (SI) equal to one millionth (1/1,000,000) of a watt (0.000001 W).
Microwatt is used to express extremely small power levels, often in microelectronics, biomedical devices, and ultra-efficient sensors.
mW to µW formula
Let’s take a closer look at the conversion formula so you can carry out these conversions independently, whether using a calculator or doing it manually with pencil and paper.
The milli- prefix in the International System of Units (SI) corresponds to a multiplier of 10-3 (0.001) while the micro- prefix represents 10-6 (0.000001).
To convert milliwatts (mW) to microwatts (µW), multiply the power value in milliwatts by 1,000.
P(µW) = P(mW) × 1,000
Or remember the mW-to-µW conversion factor: 1 mW = 1,000 µW
mW to µW conversion table
The conversion table below provides a handy reference for converting power measurement units from milliwatts (mW) to microwatts (µW). It covers commonly available power values, allowing for easy and quick conversions between these units of measurement.
| Milliwatts (mW) | Microwatts (µW) |
|---|---|
| 0.001 mW | 1 µW |
| 0.1 mW | 100 µW |
| 0.5 mW | 500 µW |
| 1 mW | 1,000 µW |
| 2 mW | 2,000 µW |
| 4 mW | 4,000 µW |
| 5 mW | 5,000 µW |
| 10 mW | 10,000 µW |
| 20 mW | 20,000 µW |
| 30 mW | 30,000 µW |
| 40 mW | 40,000 µW |
| 50 mW | 50,000 µW |
| 60 mW | 60,000 µW |
| 70 mW | 70,000 µW |
| 80 mW | 80,000 µW |
| 90 mW | 90,000 µW |
| 100 mW | 100,000 µW |
| 200 mW | 200,000 µW |
| 500 mW | 500,000 µW |
| 800 mW | 800,000 µW |
| 1,000 mW | 1,000,000 µW |
Examples
Now, let's look at an example that illustrates the calculations required to convert from milliwatts to microwatts (mW to µW).
Example: Sensor Power Consumption
Suppose you’re analyzing a medical sensor that consumes 4.25 mW of power. For precision reporting, you want the value in microwatts.
Solution
Since 1 mW = 1,000 µW, we can convert 4.25 mW to microwatts by using the following formula:
Therefore, the sensor consumes 4,250 µW of power.
To solve the problem with our calculator, follow the steps below:
- Enter the value in milliwatts: For this example, enter
4.25into theFrombox. - View the result: The converter instantly calculates and displays the equivalent value in microwatts:
4,250 mW.
FAQs
Is 1 milliwatt or 1 microwatt larger?
A milliwatt (mW) is a thousand times larger than a microwatt (µW). Here are the relationships between the units:
1 mW = 103 = 1,000 µW1 µW = 10-3 = 1 ÷ 1,000 = 0.001 mW
How to convert from milliwatts to microwatts?
To convert power from milliwatts (mW) to microwatts (µW), follow these simple steps:
- Write down the power value in milliwatts (mW).
- Multiply it by
1,000. - The result is the power in microwatts (µW).
Why do I need to convert milliwatts to microwatts?
Converting milliwatts to microwatts is essential in precision electronics and biomedical engineering. For example, ultra-low-power sensors or implants often operate in the µW range, making this unit more practical for accurate measurement.
You now know how to convert power units from milliwatts (mW) to microwatts (µW). You can quickly use our calculator to convert between the power measurement units to save time for future calculations.
