Kilobytes to Pebibytes (kB to PiB)

1 kilobyte equals 8.881784197×10⁻¹³ pebibytes (rounded).

How to convert kilobytes to pebibytes

To convert kilobytes to pebibytes, multiply the number of kilobytes by 8.881784197×10⁻¹³. The factor is rounded to 10 significant digits. To go the other way, multiply pebibytes by 1,125,899,906,843 (rounded).

pebibytes = kilobytes × 8.881784197×10⁻¹³

Example: 10 kilobytes = 8.881784197×10⁻¹² pebibytes.

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

Pebibyte (PiB)

ComputingCurrent unit

Exactly 2⁵⁰ bytes (about 1.126 petabytes).

Pebi was one of the two prefixes, with exbi, that the IEC added in January 1999 as Amendment 2 to IEC 60027-2, extending the set it approved in December 1998. The name keeps the first two letters of peta and appends bi for binary, and the symbol is PiB. It is a binary unit of exactly 2^50 bytes, or 1,125,899,906,842,624 bytes.

That is 1,024 tebibytes. Set against the decimal petabyte of 10^15 bytes, a pebibyte is about 12.6 percent larger, a gap that has grown with each prefix step from 2.4 percent at kilo. As a result, anyone who divides a 1 PB figure from a storage vendor by 2^50 will see about 0.89 PiB.

The pebibyte is useful where capacity is counted in powers of two and the exact size must be unambiguous. Wikipedia illustrates the petabyte scale as about 2,000 years of music in MP3 form.

1 pebibyte = 1.125899907×10¹⁵ bytes (approximately).

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

Related conversions

See all digital storage units.