What is a yottabyte?

From smart­phone to hard drive to your digital camera’s memory card – we store and access vast quant­it­ies of data on different devices each day. The demand for storage capacity continues to grow each year. At the same time, we’re in­creas­ingly making use of services that require access to huge volumes of data, such as video streaming services which have become firmly es­tab­lished as part of our daily lives and account for a large pro­por­tion of the world's data volumes.

Storage ca­pa­cit­ies are often specified with the unit byte and its multiples. The largest unit is the yottabyte. Although the unit of in­form­a­tion isn’t of great im­port­ance in our day-to-day life just yet, the yottabyte provides in­form­a­tion about the amount of data used globally and makes for an exciting glimpse into the future of data storage and in­creas­ing ca­pa­cit­ies.

The yottabyte is the largest existing unit for storage ca­pa­cit­ies of devices and cloud services. To un­der­stand just how big a yottabyte is, it helps to get to know the smallest units.

The smallest possible storage unit for data is one bit. This unit has two possible states: 0 or 1. But how does a bit relate to a yottabyte? To un­der­stand the re­la­tion­ship between the two sizes, it’s helpful to convert them to a byte which is made up of 8 bits. Since each bit can take on two different states, there are already 2⁸, i.e., 256 states for one byte. This helps to display a character that’s readable by humans.

The byte is followed by the units kilo-, mega-, giga-, tera-, peta-, exa-, zetta- and finally the yottabyte. Each unit is 1,024 times larger than its pre­de­cessor. A yottabyte is therefore a multiple of a byte. According to the decimal system, one yottabyte is 10²⁴ (1,000,000,000,000,000,000,000,000) bytes. However, since computers use binary values to calculate, a more precise con­ver­sion is carried out according to the binary system. This is based on the powers of two instead of the powers of ten, which is why one yottabyte cor­res­ponds to 2⁸⁰ bytes. Separate prefixes with the in­ter­me­di­ate syllable ‘bi’ exist for the binary system. The binary unit cor­res­pond­ing to the yottabyte is called the yebibyte. However, these terms (according to the binary system) have not yet es­tab­lished them­selves.

The unit byte and its multiple indicate storage ca­pa­cit­ies, typically used to denote volumes of external hard drives, USB sticks, or memory cards. The storage space of cloud providers is also specified in bytes. Con­ver­sion to bits is more common for trans­mis­sion rates. Most users are well-ac­quain­ted with specs such as ‘100 Mbit/s’ to make sense of Internet speeds. The ab­bre­vi­ation stands for a trans­mis­sion of 100 megabits per second.

In general, yot­ta­bytes can be converted to yottabits. However, this is a the­or­et­ic­al figure right now. The fastest Internet speed achieved so far is 178 terabits per second which is still far below the per­form­ance of a yottabyte.

Most sources refer to the yottabyte as the largest possible unit of data. While this is correct, and the yottabyte is currently the largest byte unit re­cog­nised by the In­ter­na­tion­al Bureau of Weights and Measures – a des­ig­na­tion for the sub­sequent unit already exists: the bron­to­byte which cor­res­ponds to 1,024 times the yottabyte. The ‘Internet of Things’ and sensor data are emerging as potential areas where this unit may come in handy.

To convert common memory ca­pa­cit­ies such as megabyte or gigabyte to yottabyte, the factor 1/1,024 is used. The following table is an overview of the con­ver­sion from yot­ta­bytes to common units of in­form­a­tion:

Day to day, hard drives offer some of the largest storage ca­pa­cit­ies. But most com­mer­cially available hardware offers storage ca­pa­cit­ies in the terabyte range. This is com­pletely suf­fi­cient for private use. Cloud providers and server farms work with even larger di­men­sions. What’s more, global data volumes continue to increase each year. Streaming services are an important driver of this growth. It’s estimated that they’re re­spons­ible for around 15 percent of all Internet traffic. In addition to the number of users, the quality of the image material continues to expand. Experts assume that global data volumes will grow to 175 zetta­bytes by 2025.

Yot­ta­bytes too are more than just a the­or­et­ic­al quantity. The American secret service NSA, for example, collects huge data quant­it­ies. The exact capacity is at least as top secret as the NSA data itself. However, experts assume that the storage capacity of the NSA data center­centre is in the yottabyte range.