How Many MB in a GB?

Megabytes and gigabytes are both storage measurement units. A gigabyte represents more capacity than a megabyte. How many MB in a GB, then? This is determined by the system used to quantify storage. You see, there are two methods when it comes to converting MB to GB.
You'll find out how this explains why there's a discrepancy between the capacity of the drive you bought and what it shows on the computer.
In this article, we'll go over the answers to these questions and more, so let's get started.

How Many MB in a GB?

There are 1,024 MB in 1GB when using the binary approach. However, as you'll see later in this article, there's a second method for quantifying storage. For the time being, here's your guide to binary prefix conversions:
  • 1TB = 1,024GB
  • 1GB = 1,024MB
  • 1MB = 1,024KB
  • 1KB = 1,024 Bytes
You'll find that your computer storage is most likely measured in hundreds of gigabytes. Solid-state drives and hard disc drives would most probably be measured in terabytes.
Storage on your phone is also measured in gigabytes to store all of your photos, apps, and messages. You'll notice that iPhones, for example, start at 64 GB.
Before we continue, we'd like to clarify something in case you're confused about the 4GB listed in your device's specifications. Storage and memory (RAM) are two things that can be measured in gigabytes.
Storage is the destination for long-term data, such as files downloaded for future use. On the other hand, memory is only there to temporarily store short-term data while the file is being used.

What Are the Two Methods for Quantifying Storage?

There are two methods for determining the exact value of a measurement unit. You can calculate this using the International System of Units (SI) or the binary approach, which is used in most electronic devices.
They're actually two different conversions with a binary and SI difference of about 4.86%.

Converting Using SI

According to SI, the “Mega” prefix is either a multiplier of 10 or a million bits. In other words, SI is the decimal system or base 10 school.
In this case, 1 kilobyte equals 1,000 bytes, which makes 1 gigabyte equal 1,000 megabytes.

Converting Using Binary System

This method is mostly used with binary devices like computers, phones, tablets, and so on. The binary system is the base 2 school. Consequently, the binary mega prefix is 1,048,576 bits, making one gigabyte equal to 1,024 megabytes.
Consider the following representations to gain a better understanding of how the binary system works:
  • 2^1 = 1
  • 2^2 = 4
  • 2^3 = 8
  • 2^4 = 16
In binary, each new digit increases the number's value by one power of two. This explains that 2^10 equals 1,024.
In fact, this is one of the reasons your hard drive reads at a lower capacity than what you purchased. Assume you purchased a 250GB external hard drive and your computer only displays 232GB of free space for use.
Now, why is that? Technically, the drive has a capacity of 250,000,000,000 bytes. To determine the exact amount of storage space available, work your way backward through measuring units.
This means you'll begin by converting bytes to kilobytes, then kilobytes to megabytes, and megabytes to gigabytes. So, multiply the total storage capacity by 1,024 three times, and you'll get 232GB.
The larger the disc capacity, the greater the difference between what’s advertised and what the computer actually reads. A 1TB drive that’s supposed to read 1,000GB will only show 931GB.

What’s the Difference Between Megabytes and Mebibytes?

You may have heard the term mebibytes several times but dismissed it as an equivalent to megabytes. The truth is that they're two different capacities depending on how they're used and converted.
We'll make a quick comparison of the two so you can tell the difference:

Megabyte (MB)

As previously stated, a megabyte is a unit of digital information storage that is widely used in computers. However, a megabyte is used exclusively to refer to the base of ten. This means that one megabyte equals 1,000,000 bytes. Alternatively, 1 gigabyte equals 1,000 megabytes.
Mega is a metric prefix used in the International System of Units (SI). SI prefixes include Kilo, Mega, Giga, Tera, Peta, Exa, Zetta, and Yotta.

Mebibyte (MiB)

A mebibyte is also a unit of measurement for computer data storage. Nonetheless, a mebibyte is unique to the binary system, which is the base of 2. This means that one mebibyte equals 1,048,576 bytes, and one gibibyte equals 1,024 mebibytes.
The prefix “mebi” is derived from the words “mega" and "binary." The International Electrotechnical Commission (IEC) developed this measuring unit in 1998. Prefixes such as Kibi, Gibi, Tebi, Pebi, Exbi, Zebi, and Yobi were also invented.
That is to distinguish between capacities indicating a power of ten and capacities indicating a power of two. Yet, until now, people have commonly referred to mebibytes as megabytes, which has become common lingo.

Bit vs. Byte

The difference between bytes and bits is another comparison that you might find useful:

Bits (b)

A bit is the smallest unit of data in computers; it's an abbreviation for binary digit. A bit has a single numeric value of zero (0) or one (1). This can be translated as on/off, true/false, plus/minus, or something similar.
It's commonly used to measure data transfer rates and is also intended to store data. When a bit is multiplied, it's referred to as a byte, and it begins to execute other instructions. As you can see, a bit is smaller than a byte, with 1 bit equaling 0.125 bytes.

Bytes (B)

A byte is another unit of data made up of 8 bits. It's the unit used by computers to represent characters such as numbers or letters. Each byte will hold on to a string of bits to execute the specified instruction.


How many MB in a GB? According to common lingo, there are 1,024 MB in 1GB. You should now have a general understanding of how storage is quantified. Based on that, you can easily calculate the capacity of your device.
You're now also aware that MiB doesn't just stand for "Men In Black" but is also a unit of measurement known as mebibytes.