When working with computers or dealing with storage, you’re likely to encounter all different types of units of information. As such, it’s easier than you’d think to get them all mixed up. Thankfully, the International System of Quantities (a.k.a. the ISQ) exists to define the units of measurement used in modern science and physics, which includes computing.
But how can you tell the difference between the units of information used in computing? Take the terabyte (TB) vs megabyte (MB), for instance. What’s the difference in size and use between these two? Let’s explain.
Terabyte (TB) vs Megabyte (MB): Side-by-Side Comparison
Terabyte | Megabyte | |
---|---|---|
Bytes | 1,099,511,627,776 bytes | 1,048,576 bytes |
Gigabytes | 1,024 gigabytes | 1/1024th of a gigabyte |
Symbols | TB, TiB | MB, MiB |
Follows | Gigabyte | Kilobyte |
Followed By | Petabyte | Gigabyte |
Terabyte (TB) vs Megabyte (MB): What’s the Difference?
Let’s go beyond this side-by-side comparison to dig a little deeper into the differences between the terabyte (TB) vs megabyte (MB). From their terminology to their equivalents to their decimal and binary notations, these are the biggest distinctions between the two units of information in computing.
Terabyte Explained
As you can see from the side-by-side comparison above, the terabyte and the megabyte are two important parts of a much larger system of units of information. What’s more, we can plainly see that the terabyte is bigger than the megabyte — much, much bigger.
In truth, one single terabyte is equivalent to more than a trillion bytes. (Bytes are one of the smallest units of information in computing, second only to the bit, which is equivalent to one single binary digit of either one [1] or zero [0].) You may see it abbreviated as either TB or TiB.

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There are two ways of defining the size of a terabyte: decimal notation, which abides by base 10 numbers, or binary notation, which is bound to base 2 numbers. In decimal notation, a terabyte is equivalent to one trillion bytes or one thousand gigabytes.
With binary notation, a terabyte is worth 1,099,511,627,776 bytes, or 1,024 gigabytes. Because of this difference of 24 gigabytes between decimal and binary notation, you might see the word “tebibyte” used to define a binary terabyte. That way, there’s no confusion regarding how much storage you’re actually working with.
Hitachi was the very first company to sell computers with 1 TB of HDD storage. This was back in 2007, marking a historic step forward in computer storage industry-wide. At the time, Hitachi made a point of noting how fast storage was changing throughout the world of computing.
It took nearly 40 years to evolve from kilobyte to megabyte, but it only took half that time to evolve from megabyte to terabyte. After Hitachi debuted their 1 TB HDD, a shockwave moved across the industry. Today, more than 15 years later, 1 TB is one of the most common storage sizes.
Megabyte Explained
Judging by the side-by-side comparison above, it’s obvious that the megabyte is significantly smaller than the terabyte. One megabyte is merely a fraction of a single gigabyte, of which there are a thousand within a single terabyte. That’s a pretty drastic difference in size, to be sure.
Regardless of whether it’s abbreviated to MB or MiB, this fact remains true: a megabyte is one of the smallest units of information you’ll encounter in your daily life, whereas the terabyte is one of the largest commonly used on a day-to-day basis.
Just as there are decimal and binary notations for the terabyte, there are also decimal and binary notations for the megabyte. In decimal notation, the megabyte is equivalent to one million bytes. In binary notation, that number increases to 1,048,576 bytes.

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To differentiate between the two, we once again have a binary-specific name to rely on: “mebibyte.” More and more in the world of computer science are leaning toward these binary names over their traditional decimal names. Alas, both “megabyte” and “mebibyte” remain standard.
The megabyte is not to be confused with the megabit, which is abbreviated as “Mb” instead of “MB.” The difference is that megabytes are used as units of information, whereas megabits are used to measure bits — or speeds — of digital information.
If these two things sound the same, then let’s phrase it another way: one megabyte is equivalent to eight megabits. In this scenario, a “byte” is used to measure size, whereas a “bit” is used to measure speed. The former is used in storage, while the latter is used in networking.
Terabyte: Real-World Examples
To better understand the true size of a terabyte, let’s look at some real-world examples of the unit of information.
Computer Storage
Whether it be HDD or SDD storage, many of today’s desktop and laptop computers come equipped with 1 TB of storage. Given the demands of the latest gaming, programming, and editing software, 1 TB is increasingly becoming the standard amount of storage across all the top brands. Even some cell phones — such as the iPhone — are coming equipped with 1 TB storage options these days.
The Human Brain
While the human brain is far from a computer, both rely on electrical signals to send and receive messages. With this in mind — no pun intended — it’s interesting to note that the human brain is believed to have a memory size of about 1.25 TB. While it’s hardly a direct correspondence, it nevertheless helps to put the terabyte into perspective.
Megabyte: Real-World Examples
Now, let’s examine some real-world examples of the megabyte, just as we’ve done for the terabyte.
File Sizes
Whether you’re dealing with a laptop, a desktop, or even a smartphone, many of the most common files we send and receive daily are measured in megabytes. For instance, a single high-quality JPG at 300 PPI will measure in at around 3 or 4 MB.
A novel-sized PDF, depending on the length, will come in around 1 to 3 MB. A one-minute audio file typically comes in around 1 MB.
Mobile Data
Today, cellular data is measured in gigabytes. But, as we know, a gigabyte is made up of around a thousand megabytes. So, if you only have 5 GB of data a month, it helps to know how many megabytes certain activities take up.
Streaming an hour of music will take up about 40-100 MB of mobile data, depending on the quality of the audio. Half an hour of Netflix will take up around 400 MB.
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