What does exabyte mean?
An exabyte is a unit of digital information equal to one billion gigabytes, or 1 followed by eighteen zeros bytes (10^18). It sits far up the ladder of SI-prefixed data units, beyond the terabyte and petabyte, and exists because modern data volumes have outgrown smaller measures: global internet traffic, large cloud providers' archives, and national-scale datasets are routinely described in exabytes. The word combines the prefix 'exa-', from the Greek 'hex' meaning six (marking the sixth power of a thousand), with 'byte', the standard unit of digital storage. Because binary and decimal counting diverge at this scale, the International Electrotechnical Commission distinguishes the exabyte from the exbibyte, which equals 2^60 bytes. Though technical in origin, the term also appears figuratively to convey almost unimaginable abundance of information.
nounA unit of digital information equal to one quintillion (10^18) bytes, or, in binary reckoning, 2^60 bytes (an exbibyte). It is used chiefly in computing and data science to describe very large volumes of data.
- A unit of data storage equal to 10^18 bytes, used to quantify extremely large amounts of digital information.
- Informally, an enormous quantity of anything digital or informational.
"The world's data centers now store tens of exabytes of information."
"Global internet traffic is projected to reach hundreds of exabytes per year."
"Backing up the research archive required nearly half an exabyte of storage."
Regular plural; commonly preceded by a numeral or quantifier such as 'several' or 'hundreds of'.
"The network transmits several exabytes of traffic every month."
All the words ever spoken by humans would fit in roughly five exabytes of text — a single exabyte is already more than most nations produce in years.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of exabyte
The word 'exabyte' was coined in the late twentieth century from 'exa-', the SI prefix adopted in 1975 denoting 10^18, combined with 'byte', itself a mid-1950s coinage from 'bit'. The prefix derives ultimately from the Greek 'hex', meaning six, chosen because 1000^6 equals ten to the eighteenth power. It shares this root with other magnitude terms such as terabyte, petabyte, and zettabyte, all built on the same pattern of prefix plus byte.
Related word forms
How exabyte is actually used
Exabyte belongs to formal, technical register, appearing mainly in computing, data-center engineering, and scientific reporting. In everyday speech it signals scale rather than precision; note that some vendors use it loosely for 2^60 bytes, which standards bodies designate as an exbibyte.
Easily confused with exabyte
An exabit is one quintillion bits, whereas an exabyte is one quintillion bytes — eight times larger, since a byte comprises eight bits.
An exbibyte is a binary unit of 2^60 bytes (about 1.15 exabytes), while an exabyte is the decimal unit of 10^18 bytes.