This article will show how to convert electrical resistance measurement units from ohms (Ω) to megaohms (MΩ). We will cover essential definitions, provide examples, share relevant formulas, and present tables, along with answers to common questions.
Definitions of Ohm and Megaohm
Let’s get started by understanding the key definitions of Ohm (Ω) and Megaohm (MΩ). Understanding these terms will allow you to perform conversions confidently.
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 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.
Ω 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) represents a multiplier of 106 (1,000,000). So, to convert from ohms to megaohms, divide the number of ohms (R(Ω)) by 106 (1,000,000).
R(MΩ) = R(Ω) ÷ 106 = R(Ω) ÷ 1,000,000
Or remember the Ω-to-MΩ conversion factor: 1 Ω = 10-6 = 0.000001 MΩ
Ω to MΩ conversion table
The conversion table below provides a handy reference for converting electrical resistance measurement units from ohms (Ω) to megaohms (MΩ). It covers a range from 0.1 Ω to 1,000 Ω, allowing for easy and quick conversions between these units of measurement.
| Ohms (Ω) | Megaohms (MΩ) |
|---|---|
| 0.1 Ω | 0.0000001 MΩ |
| 0.5 Ω | 0.0000005 MΩ |
| 1 Ω | 0.000001 MΩ |
| 2 Ω | 0.000002 MΩ |
| 4 Ω | 0.000004 MΩ |
| 5 Ω | 0.000005 MΩ |
| 10 Ω | 0.00001 MΩ |
| 20 Ω | 0.00002 MΩ |
| 30 Ω | 0.00003 MΩ |
| 40 Ω | 0.00004 MΩ |
| 50 Ω | 0.00005 MΩ |
| 60 Ω | 0.00006 MΩ |
| 70 Ω | 0.00007 MΩ |
| 80 Ω | 0.00008 MΩ |
| 90 Ω | 0.00009 MΩ |
| 100 Ω | 0.0001 MΩ |
| 200 Ω | 0.0002 MΩ |
| 500 Ω | 0.0005 MΩ |
| 800 Ω | 0.0008 MΩ |
| 1,000 Ω | 0.001 MΩ |
Examples
Now, let's look at an example that illustrates the calculations required to convert from ohms to megaohms (Ω to MΩ).
Example: High-Voltage Equipment Insulation Testing
Electrical safety tests on high-voltage equipment measure insulation resistance in ohms. Converting these values to megaohms simplifies evaluation.
If an insulation test shows 2,500,000 Ω, what is the resistance in megaohms? You need it to assess equipment safety.
Solution
Since 1 megaohm (MΩ) = 106 = 1,000,000 ohms (Ω), we can convert 2,500,000 Ω to megaohms by using the following formula:
Therefore, the 2,500,000 Ω electrical resistance is equivalent to 2.5 MΩ.
To solve the problem with our calculator, follow the steps below:
- Enter the value in ohms: For this example, enter
2,500,000into the From box. - View the result: The converter instantly calculates and displays the equivalent value in megaohms:
2.5 MΩ.
FAQs
Is 1 ohm or 1 megaohm larger?
A megaohm (MΩ) is a million times bigger than an ohm (Ω). Here are the relationships between the units:
1 MΩ = 106 = 1,000,000 Ω1 Ω = 10-6 = 1 ÷ 1,000,000 = 0.000001 MΩ
How to convert from ohms to megaohms?
To convert electrical resistance from ohms (Ω) to megaohms (MΩ), follow these simple steps:
- Step 1: Write down the electrical resistance value in ohms (Ω).
- Step 2: Divide it by
1,000,000. - Step 3: The result is the value of the electrical resistance in megaohms (MΩ).
Why do I need to convert ohms to megaohms?
Converting ohms to megaohms is important when dealing with very high resistance values. When the numbers become very large, expressing them in megaohms simplifies the measurement and reduces the risk of misreading or misreporting them.
For example, rather than writing 50,000,000 Ω, converting this value to 50 MΩ avoids a long string of zeros and makes the reading clearer. This makes comparisons and analyses clearer, reduces the chance of misinterpretation, and aligns with industry standards for documentation and communication.
You now know how to convert electrical resistance from ohms (Ω) to megaohms (MΩ). You can quickly use our calculator to convert between the electric resistance measurement units to save time for future calculations.
