This article will show how to convert electrical resistance measurement units from megaohms (MΩ) to milliohms (mΩ). We will cover essential definitions, provide examples, share relevant formulas, and present tables, along with answers to common questions.
Definitions of Ohm, Megaohm, and Milliohm
Let’s get started by understanding the key definitions of Ohm (Ω), Mega-ohm (MΩ), and Milli-ohm (mΩ). Understanding these terms will enable you to perform conversions with confidence.
What is Ohm?
The ohm (Ω) is the SI derived unit of electrical resistance. It is defined as the resistance between two points of a conductor when a constant potential difference of one volt is applied across those points, producing a current of one ampere in the conductor, assuming no additional electromotive force is present.[1]
According to SI prefixes[2], which are based on powers of 10, an ohm (1 Ω) is equivalent to one millionth (1/1,000,000) of a megaohm (10-6 MΩ or 0.000001 MΩ).
What is Milliohm?
A milliohm (mΩ) is a unit of electrical resistance in the SI system equal to one thousandth (1/1,000) of an ohm (10-3 Ω).
It is commonly used in fields such as power distribution, precision electronic testing, and industrial motor evaluation. Accurately measuring very low resistance values is essential for determining the efficiency and reliability of these systems.
What is Megaohm?
A megaohm (MΩ) is a unit of electrical resistance in the SI system equal to one million (1,000,000) ohms (106 Ω).
It is commonly used in high-voltage insulation testing, medical device safety validation, and industrial sensor design, where measuring extreme resistance up to millions of ohms determines critical safety margins and operational reliability.
MΩ to mΩ 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 mega- prefix in the International System of Units (SI) corresponds to a multiplier of 106 (1,000,000) while the milli- prefix represents 10-3 (0.001).
To convert megaohms (MΩ) to milliohms (mΩ), multiply the resistance value in megaohms by 109 (1,000,000,000), since 1 megaohm equals 1,000,000,000 milliohms.
R(mΩ) = R(MΩ) × 109 = R(MΩ) × 1,000,000,000
Or remember the MΩ-to-mΩ conversion factor: 1 MΩ = 109 = 1,000,000,000 mΩ
MΩ to mΩ conversion table
The conversion table below provides a handy reference for converting electrical resistance measurement units from megaohms (MΩ) to milliohms (mΩ). It covers a range from 0.1 MΩ to 1,000 MΩ, allowing for easy and quick conversions between these units of measurement.
| Megaohms (MΩ) | Milliohms (mΩ) |
|---|---|
| 0.1 MΩ | 100,000,000 mΩ |
| 0.5 MΩ | 500,000,000 mΩ |
| 1 MΩ | 1,000,000,000 mΩ |
| 2 MΩ | 2,000,000,000 mΩ |
| 4 MΩ | 4,000,000,000 mΩ |
| 5 MΩ | 5,000,000,000 mΩ |
| 10 MΩ | 10,000,000,000 mΩ |
| 20 MΩ | 20,000,000,000 mΩ |
| 30 MΩ | 30,000,000,000 mΩ |
| 40 MΩ | 40,000,000,000 mΩ |
| 50 MΩ | 50,000,000,000 mΩ |
| 60 MΩ | 60,000,000,000 mΩ |
| 70 MΩ | 70,000,000,000 mΩ |
| 80 MΩ | 80,000,000,000 mΩ |
| 90 MΩ | 90,000,000,000 mΩ |
| 100 MΩ | 100,000,000,000 mΩ |
| 200 MΩ | 200,000,000,000 mΩ |
| 500 MΩ | 500,000,000,000 mΩ |
| 800 MΩ | 800,000,000,000 mΩ |
| 1,000 MΩ | 1,000,000,000,000 mΩ |
Examples
Now, let's look at an example that illustrates the calculations required to convert from megaohms to milliohms (MΩ to mΩ).
Example: Industrial Machine Wiring Repair
In an industrial facility, aging machine wiring began to show signs of insulation breakdown. The measured resistance was 0.34 MΩ. Converting this measurement to milliohms helped the maintenance team identify the severity of the degradation for repair planning.
What is 0.34 MΩ in milliohms?
Solution
Since 1 megaohm (MΩ) = 109 = 1,000,000,000 milliohms (mΩ), we can convert 0.34 MΩ to milliohms by using the following formula:
Therefore, the 0.34 MΩ electrical resistance is equivalent to 340,000,000 mΩ.
To solve the problem with our calculator, follow the steps below:
- Enter the value in megaohms: For this example, enter
0.34into the From box. - View the result: The converter instantly calculates and displays the equivalent value in milliohms:
340,000,000 mΩ.
FAQs
Is 1 megaohm or 1 milliohm larger?
A megaohm (MΩ) is a billion times bigger than a milliohm (mΩ). Here are the relationships between the units:
1 MΩ = 109 = 1,000,000,000 mΩ1 mΩ = 10-9 = 1 ÷ 1,000,000,000 = 0.000000001 MΩ
How to convert from megaohms to milliohms?
To convert electrical resistance from megaohms (MΩ) to milliohms (mΩ), follow these simple steps:
- Step 1: Write down the electrical resistance value in megaohms (MΩ).
- Step 2: Multiply it by a billion (
109or1,000,000,000). - Step 3: The result is the value of the electrical resistance in milliohms (mΩ).
Why do I need to convert megaohms to milliohms?
Converting megaohms to milliohms is important when you need to analyze extremely high resistance with very fine resolution. Megaohm values are very large, which can hide small changes that might be critical during repairs or diagnostics.
Converting them to milliohms makes these subtle variations more apparent and easier to analyze. It also ensures that readings match the resolution of some high-precision instruments and documentation standards used in repair and maintenance settings.
You now know how to convert electrical resistance from megaohms (MΩ) to milliohms (mΩ). You can quickly use our calculator to convert between electric resistance measurement units, saving time for future calculations.
