Exabyte Definition

April 8, 2024

An exabyte is a unit of digital information storage that equals approximately one billion gigabytes (GB) or one quintillion bytes (1,000,000,000,000,000,000 bytes). The prefix "exa" is part of the International System of Units (SI) and represents 10 to the power of 18 (10^18).

An exabyte is a massive scale of measurement, often used to discuss data storage at the scale of large data centers, cloud storage services, and the global internet data traffic. Given the vast amount of data generated and stored worldwide, the term exabyte is increasingly common when discussing the scale of big data and the capacity required for its storage and management.

Exabyte vs. Other Storage Sizes

Here is an overview of comparisons between exabytes and other storage sizes.


An exabyte represents a colossal amount of data, equivalent to one quintillion bytes or 10^18 bytes. It's a scale of measurement that transcends the familiar terabyte (10^12 bytes) commonly used to describe the capacity of consumer hard drives. Exabytes are used to quantify the enormous volumes of data handled by global data centers and cloud storage providers and to articulate the sheer scale of the digital universe in the age of big data. The magnitude of an exabyte allows for the storage of billions of high-definition videos, extensive databases of genomic sequences, and the expansive data generated by Internet of Things (IoT) devices.


A petabyte is a measure of data storage capacity that is equivalent to 1,024 terabytes or one quadrillion bytes (10^15 bytes). This unit of measurement is one step below an exabyte in the hierarchy of data sizes. Petabytes are widely used to discuss the capacity of large data storage systems and networks, particularly for enterprise-level storage solutions, large-scale cloud services, and extensive multimedia libraries. A petabyte can store hundreds of thousands of hours of high-definition video or the content of millions of books, making it a suitable scale for libraries, large-scale digital archives, and backup systems for organizational data.


A terabyte, equivalent to 1,024 gigabytes or one trillion bytes (10^12 bytes), is a more commonly encountered unit of digital storage, readily comprehensible to the general public. It is the go-to measurement for hard drive sizes in personal computers, external storage devices, and mid-sized data collections. In practical terms, a terabyte can hold around 250,000 high-quality MP3 files, approximately 300 hours of high-definition video, or hundreds of high-resolution video games.


A gigabyte is a unit of storage measuring approximately one billion bytes or 10^9 bytes. It is one of the most commonly used units of digital information, reflecting a size convenient for measuring the storage capacity of smartphones, tablets, and lower-end or older hard drives. A gigabyte can store about 230 typical MP3 songs, an hour of standard-definition video, or hundreds of high-quality photographs. In the context of daily digital use, gigabytes serve as a practical measure of storage for applications, personal documents, and media.

Why Companies Need Exabyte of Storage?

Here are key reasons why companies might need exabyte-level storage:

  • Big data analytics and artificial intelligence (AI). Many companies leverage big data analytics and AI to gain insights into customer behavior, market trends, and operational efficiency. These technologies require access to vast datasets to train machine learning models and perform complex analyses, which can easily reach exabyte scales in industries like social media, ecommerce, and multimedia content providers.
  • Internet of Things (IoT). With the proliferation of IoT devices in industries such as manufacturing, healthcare, and smart cities, the amount of data generated is enormous. Each device continuously produces data that, when aggregated over millions of devices, accumulates to exabyte-scale datasets. These datasets are crucial for monitoring, real-time decision-making, and predictive maintenance.
  • Digital content and media. The media and entertainment industries produce a significant volume of high-definition video content, including movies, TV shows, and user-generated content. Storing and streaming this content requires immense storage capacities, often reaching the exabyte level, to ensure high availability and quality of service to global audiences.
  • Archiving and compliance. Regulatory requirements in many industries, such as finance and healthcare, mandate long-term data retention for legal compliance and auditing purposes. As the volume of financial transactions, communication records, and healthcare patient records grows, so does the need for storage capable of handling exabyte-scale archives.
  • Scientific research and genomics. Fields such as genomics, climate science, and particle physics generate vast amounts of data from experiments, simulations, and observations. For instance, genomics research involves sequencing and analyzing the DNA of numerous organisms, requiring substantial storage capacity to accommodate the resulting data, which can easily exceed petabytes and approach exabytes for large-scale studies.
  • Cloud services and data centers. Cloud storage providers and data center operators must scale their infrastructure to offer services to millions of users and businesses. As cloud computing becomes more prevalent, these providers need to manage exabytes of data efficiently to support a wide range of services, from web hosting and online applications to backup and disaster recovery solutions.

Anastazija is an experienced content writer with knowledge and passion for cloud computing, information technology, and online security. At phoenixNAP, she focuses on answering burning questions about ensuring data robustness and security for all participants in the digital landscape.