How many MB are there in a GB?

Whether it’s your mobile data plan, the amount of storage in a phone, hard drive, laptop, or something else, you’ll see GBs and MBs in many places.

If you just want an answer to the question you just searched for, there are 1024 MB (megabytes) in a GB (gigabyte). There are 1024 gigabytes in a terabyte (TB) and 1024 terabytes in a petabyte (PB).

These are all storage capacities and can refer to memory (RAM), the amount of data you can use per month over 4G or 5G, and the hard drive or SSD capacity of your PC or laptop.

Sure, that’s great knowing that 1024MB = 1GB, but what does that mean? Is 5 GB per month enough for a mobile data plan? Is a 500 GB hard drive big enough to store your files?

This is what we will explain here, as well as the conversion between MB, GB, TB and the difference between megabytes and megabits.

What is a megabyte?

Computer storage is measured in gigabytes (GB) and terabytes (TB), among other units. Your phone will have a number of gigabytes in which to store apps, music, contacts, emails, messages, photos, videos and more.

It’s easy to confuse storage and memory. Memory, or RAM, exists to temporarily store files and data while they are in use. This is why the amount of RAM is much smaller – a phone might have 128GB of storage but only 4GB of RAM.

Your PC or laptop hard drive will likely have hundreds of gigabytes of storage space. External hard drives and network-attached storage (NAS) can have a similar capacity or even thousands of gigabytes, called terabytes (TB).

Here’s how it all works:

1 TB = 1024 GB
1 GB = 1024 MB
1 MB = 1024 KB
1 KB = 1024 bytes
1 byte = 8 bits
1 bit = 0 or 1

Note: This does not cover SI units, which operate on the basis that kilo means 1000. This means that there are two different approaches to quantifying storage, one that uses the power of two (shown above) and the other which uses the power of ten which makes 1 KB = 1000 bytes.

This is why you will see kilobytes called kibibytes and megabytes called mibibytes in order to differentiate between them. However, most people still use Megabytes to mean 1024 kiloBytes even though they really should say MibiBytes, and the same with GB and TB.

Computers operate using the power of two, not the power of 10, because they are binary machines, which is why the power of two should be applied to computers (and phones, tablets, and other electronic gadgets).

Here is a more detailed explanation, with examples.

Bit: Computers deal with binary digits, or bits for short. A bit can be 0 or 1, equivalent or disabled or enabled.

Byte: A byte is eight binary digits, such as 1111001.

Kilobytes (kb): The smallest file stored on a smartphone, tablet or PC is usually four kilobytes (4 KB) in size. A kilobyte is 1024 bytes. Therefore, 1 KB equals 1024 x 8 = 8192 binary digits.

Megabyte (MB): 1024 KB equals one megabyte (MB).

Gigabyte (GB): There are 1024 MB in a gigabyte.

Terabyte (TB): There are 1024 GB in a terabyte (TB)

How much storage do I need?

It depends on what you want to store. Documents take up very little space. Maybe 20 KB for a Word document without images. A typical three-minute song in MP3 format can take up 5MB, a photo can be about the same, while a one-hour video can take up between 500MB and 10GB.

Video is the file type that takes up the most space, but the amount depends on its resolution and format. The most common format is still MP4, but it’s impossible to say how much storage you’d need per minute of video unless you also know the resolution, bitrate, and other details.

Whether a 64GB iPhone, 200GB of iCloud storage, or a 1TB hard drive is big enough again depends on whether you need to store lots of music, videos, and photos — and apps.

The truth is, the more storage you have, the better, and you’ll never regret buying a bigger phone or laptop.

Why your hard drive has less capacity than advertised

Hard drive manufacturers have long avoided the power of two to the power of ten system. Some say it’s a clever marketing ploy, but whatever the reason, it creates some confusion depending on what operating system you’re plugging it into. Linux uses decimal these days, while Windows 10 uses units of the power of two.

This means that 1000 bytes = 1 kilobyte and 1000 kilobytes = 1 MB. Again, 1000 MB = 1 GB and 1000 GB = 1 TB.

Windows treats a 250 GB hard drive as 232 GB and a 1 TB drive as 931 GB. (The SSD above has an unusual capacity of 977 GB, or 1049 Gibibytes.)

Usually a 1TB hard drive has the capacity to store 1,000,000,000,000 bytes. Divide that by 1024 and you get 976,562,500 KB. Divide again by 1024 and you get 953,674.3 MB. Finally, divide by 1024 to get gigabytes and you get 931.32 GB.

Also keep in mind that if a device – like a phone or tablet – claims to have, say, 64GB of storage, that’s not the usable amount. That’s the total, and some of it will be used for the operating system and leave you with a smaller amount to use for apps, photos, videos, and files.