What is Gigabyte (GB)? (Explained)

What is Gigabyte (GB)?

A gigabyte, typically abbreviated as GB, is a unit of measurement for data. This unit is used to define the storage and the file size.

According to the metric system, one gigabyte is equal to 2 to the 30th power, which is equivalent to 1,073,741,824 bytes or 1,024 megabytes.


  • Gigabyte is the unit to measure the data holding capacity of a storage unit. The unit symbol is GB.
  • Coupled with time in seconds and represented as GB/s, it is also used to denote the read and write speeds of the storage units.
  • This particular measurement can be represented in both the decimal and binary systems and is used to measure document, audio, or video files.
  • Gigabyte is often used by companies that need to handle sufficiently large amounts of data such as private companies for their intranets, Local Area Networks, wireless telecommunication, and the public internet.
  • Gigabyte and gigabit are both related to data measurement but are not the same. While, the former measures the data holding capacity and read and write speed, the latter measures speed of data travel across networks.

Understanding Gigabyte

What is Gigabyte (GB)

The gigabyte is typically a multiple of a byte used for digital information, where the prefix ‘giga’ implies 109 according to the International System of Units (SI). The unit symbol for one gigabyte is GB.

In simple words, a gigabyte is equal to one billion or 109 bytes.

It is quite a large amount of data, considering the fact that a bit is the smallest unit of data in binary computer code involving either a 0 or a 1, and eight such bits make one single byte.

This particular unit of data measurement is used to measure a sufficiently large amount of data stored in the files used across different platforms such as:

  • The public internet
  • Intranets of private companies
  • Wireless telecommunication networks
  • Local Area Network (LAN)

Just like other multiples of bytes, such as kilobyte and megabyte, gigabyte is also used to measure data for the following:

  • Documents
  • Photos
  • Videos

However, the number of files in one gigabyte may not be the same for all of the above. This is because it depends on specific factors such as:

  • The type of the files
  • Their respective sizes
  • The resolution

Common equivalents

One gigabyte of data is equal to the following lower standard measurements:

  • 1,000,000,000 bytes in the decimal system and 1,073,741,824 bytes in the binary system
  • 1,000,000 kilobytes in the decimal system and 1,048,576 kilobytes in the binary system
  • 1,000 megabytes in the decimal system and 1,024 megabytes in the binary system
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And, some of the larger data capacity measurement units with respect to gigabyte are as follows:

  • One terabyte is equal to 1,000 gigabytes in the decimal system and 1,024 gigabytes in the binary system
  • One petabyte is equal to 1,000,000 gigabytes in the decimal system and 1,048,576 gigabytes in the binary system
  • One exabyte is equal to 1,000,000,000 gigabytes in the decimal system and 1,073,741,824 gigabytes in the binary system


Typically, the estimates can be very broad. However, the following examples will give you a fair idea about it:

  • In a Word file, the number of documents typically depends on the page length, but it can normally range anywhere between 2 and 10,000, or even more.
  • In the case of a video file, it depends on the video compression, resolution and video minutes, but may typically range anywhere between 1.5 and 3.5 minutes.
  • As for an image file, it depends on the size of the image and resolution, but may typically range anywhere between one and one thousand.
  • The audio files also vary in measurement and it depends on the length of the songs or podcasts, but may typically range between 250 and 350 pieces of music.

A few other examples of the magnitude of storage based on gigabytes are:

  • An hour of Standard Definition Television or SDTV video at 2.2 Mbit/s will take up about 1 GB of storage space on the unit.
  • Only seven minutes of High Definition Television or HDTV video at 19.39 Mbit/s will consume roughly 1 GB of storage space on the unit.
  • An uncompressed CD-quality audio file of about 114 minutes at 1.4 Mbit/s will need about 1 GB of space on the hard disk for storing it.
  • A single layer DVD+R disc and a dual-layer DVD+R disc can hold data of about 4.7 GB and 8.5 GB, respectively.
  • A single layer Blu-ray disk, in comparison, can store about 25 GB of data, while a double-layer disc can hold roughly 50 GB of data on it but a triple-layered Ultra HD Blu-ray disc can store approximately 100 GB of data.
  • A relatively large Nintendo Switch cartridge can hold about 32 GB of data.

Typically, gigabyte is used to denote the capacity of holding data by the faster storage devices such as the Solid State Drives (SSDs) because it is considered to be a pretty fast rate of processing data, which is, however, denoted as GB/s.

For example, if a storage device is marked 2 GB/s, it indicates that its read and write speed is 2 GB/s.

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Apart from that, even the Random Access Memory (RAM) is measured in gigabytes as well, for example, 1 GB of RAM, 2 GB of RAM, and so on.

However, you are not supposed to mix gigabytes with gigabits, even though both are units of measurements used extensively in the world of computers.

A gigabyte typically measures the data storage capacity and the file size. On the other hand, a gigabit, usually abbreviated as Gb, represents the rate at which the data is moving across a network.

How Long Can 1 GB Last?

Well, it all depends on the type of data you want to use it for. Ideally, 1 GB is simply not enough and will be used up soon in most cases, often in less than an hour.

Today, when the workload is mostly based on digital data usage, it will not take a long time to consume a gigabyte of data.

For example, even an average user of a phone looks for at least 4.5 GB of mobile data every month.

Different tasks consume variable amounts of data to work. While some may consume just a few megabytes in an hour, a few other activities may need a couple of gigabytes to function.

Please note that these may vary depending on the device models and configurations.

Here are some specific activities with their estimated time and data consumption. Based on these measurements you can very well judge how long a gigabyte would last.

  • Browsing the internet may require using 60 MB of data per hour.
  • Listening to music may need about 11 MB of data per hour at 24 kbps, 43 MB per hour at 96 kbps, 72 MB per hour at 160 kbps, and 144 MB per hour at 320 kbps.
  • Watching a movie on Netflix may consume up to 1 GB of data per hour if you watch it in standard definition, and up to about 3 GB per hour if you watch it in HD.
  • Watching any other video on YouTube at 1080p resolution may consume a bit more than 1.50 GB of data in an hour, but watching it in 4K will need nearly 3 GB of data per hour.
  • If you simply browse or scroll social media, your system will consume up to 90 MB of data per hour as opposed to 156 MB in an hour when you are interacting on any platform.
  • Chatting through Skype and other media may consume data within the range of 180 MB per hour to 270 MB per hour.

If you cannot calculate the time one GB of data would last for the above activities on your system based on the rates mentioned, here it is for you.

  • It will take a little more than 16 hours while browsing the internet.
  • While listening to music it will last for a little more than 92 hours at 24 kbps, 23 hours at 96 kbps, 13 hours at 160 kbps, and 8 hours at 320 kbps.
  • Watching a movie on Netflix will consume 1 GB of data in about an hour while watching it on SD and about 20 minutes while watching an HD movie.
  • Watching regular YouTube videos at 1080p will consume a gigabyte of data in a little more than 30 minutes and in about 20+ minutes while watching them in 4K resolution.
  • One GB of data will last for about 11 hours if you simply scroll through the social media pages and less than 7 hours while interacting with others on the platform.
  • Using Skype, FaceTime and other platforms will consume a gigabyte of data in a little more than 3 to 5 hours.
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In order to give you even a better idea, here are a few more concrete examples of how much a gigabyte of data will be equal to and last for:

  • 250 song downloads
  • 6,180 emails received and sent
  • 3,333 normal emails with attachments of average size
  • 50,000 regular emails without any attachments in them
  • 250 photos at 10 megapixels
  • 5 hours of SD movies
  • 353 YouTube videos of one-minute duration


  • One gigabyte is equal to 1024 megabytes, but in comparison, one megabyte is equal to 1024 kilobytes. This means that a gigabyte is bigger than a megabyte.
  • In terms of bytes, one gigabyte is equal to one billion bytes, but in comparison, one megabyte is equal to one million bytes.


A gigabyte consists of several bytes and measures the amount of data or digital information.

Denoted by GB, in the world of computer science and IT, one gigabyte of data is equal to 1,000,000,000 bytes or 1,000 megabytes.

It is greater than an MB and smaller than a TB, which are used to measure storage capacity.

About Puja Chatterjee

Puja ChatterjeePuja Chatterjee is a technical writer with extensive knowledge about computers. She graduated from BIMS. Her expertise includes technology writing and client relationship management gained through over 12 years of experience. Follow Her at Linkedin.

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