How Many MB are 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 GB and MB in many places.

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

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

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

That’s what we’ll explain here, as well as how to convert between MB, GB, TB and the difference between megabytes and megabits.

What’s 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 get confused about storage and memory. Memory, or RAM, exists to store files and data temporarily while they’re being used. That’s why the amount of RAM is much smaller – a phone might have 128GB of storage but only 4GB of RAM.

The hard drive in your PC or laptop will probably have hundreds of gigabytes of storage space. External hard drives and network attached storage (NAS) might have a similar capacity or even thousands of gigabytes, which are called terabytes (TB).

Here’s how it all works:

• 1TB = 1024GB
• 1GB = 1024MB
• 1MB = 1024KB
• 1kB = 1024 Bytes
• 1 Byte = 8 bits
• 1 bit = 0 or 1

Note: this doesn’t cover SI units, which work on the basis that kilo means 1000.. This means there are two different approaches to quantifying storage, one which uses the power-of-two (shown above) and the other which uses the power-of-ten which makes 1KB = 1000 Bytes.

That’s why you’ll see kilobytes referred to as kibibytes and Megabytes as mibibytes in order to differentiate them. However, most people still use Megabytes to mean 1024 kiloBytes even if they really should say MibiBytes, and the same with GB and TB.

Computers work using the power of two, not the power of 10, because they’re binary machines, which is why the power-of-two should be applied to computers (and phones, tablets and any other electronic gadget).

Here’s 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 off or on.

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

Kilobyte (kB): The smallest file stored on a smartphone, tablet or PC is typically four kilobytes (4KB) in size. A kiloByte is 1024 Bytes. Therefore 1KB is the same as 1024 x 8 = 8192 binary digits.

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

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

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

How much storage do I need?

It depends on what you want to store. Documents take up very little space. Maybe 20KB for a Word document with no images in it. A typical three-minute song in MP3 format might take up 5MB, a photo could be about the same, while an hour-long video could be between 500MB and 10GB.

Video is the type of file that takes up the most space, but how much 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 upon whether you need to store lots of music, videos and photos – and apps.

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

Why your hard drive has a lower capacity than advertised

Hard drive manufacturers have long eschewed the power-of-two system for the power of ten. Some say it’s a clever marketing ploy, but whatever the reason, it makes for some confusion depending upon which operating system you connect it to. Linux uses decimal these days, while Windows 10 uses power-of-two units.

This means that 1000 Bytes = 1 kiloByte and 1000 kiloBytes = 1MB. Again, 1000MB = 1GB and 1000GB = 1TB.

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

Usually a 1TB hard drive has the capacity to store 1,000,000,000,000 Bytes. Divide this by 1024 and you get 976,562,500KB. Divide by 1024 again and you get 953,674.3MB. Finally, divide by 1024 to get Gigabytes and you end up with 931.32GB.

Remember too, that if a device – such as 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 a lower amount available for you to use for apps, photos, videos and files.