Kilobytes to Yottabytes (kB to YB)

1 kilobyte equals 1×10⁻²¹ yottabytes exactly.

1 kilobyte = 1×10⁻²¹ yottabytes

How to convert kilobytes to yottabytes

To convert kilobytes to yottabytes, multiply the number of kilobytes by 1×10⁻²¹. This factor is exact. To go the other way, multiply yottabytes by 1×10²¹.

yottabytes = kilobytes × 1×10⁻²¹

Example: 10 kilobytes = 1×10⁻²⁰ yottabytes.

Decimal prefixes (kB, MB, GB) are powers of 1,000; binary prefixes (KiB, MiB, GiB) are powers of 1,024. Storage makers use decimal; Windows reports binary but labels it GB.

About these units

Kilobyte (kB)

ComputingCurrent unit

1,000 bytes in the SI (decimal) definition. Older software and Windows sometimes use KB to mean 1,024 bytes; see kibibyte.

Few units have had two meanings for so long. By the mid-1960s most computers used binary addressing, so memory sizes came in powers of two and engineers borrowed kilo to mean 1,024. IBM documentation for the System/360 in 1964 used an uppercase K for 1,024. Hard disk makers took a different path from the start. The IEC later settled the question: kilobyte, symbol kB, means 1,000 bytes, and 1,024 bytes is a kibibyte.

Floppy disks show the muddle. The Shugart SA-400 of 1976 held 109,375 bytes unformatted and was advertised as 110 Kbyte, the decimal way, while a 1978 Tandon double-density disk held 368,640 bytes, or 360 times 1,024, and was sold as 360 KB. Windows still divides by 1,024, so a 65,536-byte file appears as 64 KB there, while Mac OS X Snow Leopard and later would call it 66 kB. A kilobyte is also tiny: Edgar Allan Poe's The Cask of Amontillado is 12,843 bytes.

1 kilobyte = 1,000 bytes (exactly).

Sources: Wikipedia: Kilobyte; Wikipedia: Binary prefix; NIST: Prefixes for binary multiples

Yottabyte (YB)

ComputingCurrent unit

10²⁴ bytes. Yotta was the largest SI prefix until ronna and quetta were added in 2022.

Yotta stands for the eighth power of 1,000 and was adopted in 1991, so a yottabyte is 10^24 bytes, or 1,000 zettabytes. It stood at the top of the SI prefix list until 2022, when the BIPM added ronna (10^27) and quetta (10^30), and the byte forms, ronnabyte and quettabyte, followed. The symbol is YB.

No storage system or traffic measure approaches this size. Global IP traffic in 2016 was only around 1.2 zettabytes a year, about one-thousandth of a yottabyte, so the unit has mostly served in forecasts and illustrations rather than measurement.

The binary yobibyte (YiB) is 2^80 bytes, which is 1,208,925,819,614,629,174,706,176 bytes and about 20.9 percent more than a yottabyte. IEC standards define byte multiples up to this level, and a gap that wide is why the decimal and binary names are worth keeping apart.

1 yottabyte = 1×10²⁴ bytes (exactly).

Sources: Wikipedia: Byte; Wikipedia: Metric prefix; Wikipedia: Zettabyte Era

Related conversions

See all digital storage units.