Kilobytes to Exbibytes (kB to EiB)

1 kilobyte equals 8.67361738×10⁻¹⁶ exbibytes (rounded).

How to convert kilobytes to exbibytes

To convert kilobytes to exbibytes, multiply the number of kilobytes by 8.67361738×10⁻¹⁶. The factor is rounded to 10 significant digits. To go the other way, multiply exbibytes by 1.152921505×10¹⁵ (rounded).

exbibytes = kilobytes × 8.67361738×10⁻¹⁶

Example: 10 kilobytes = 8.67361738×10⁻¹⁵ exbibytes.

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

Exbibyte (EiB)

ComputingCurrent unit

Exactly 2⁶⁰ bytes (about 1.153 exabytes).

Exbi joins the first two letters of exa to bi, for binary, and was published by the IEC in January 1999 with pebi. An exbibyte (EiB) is exactly 2^60 bytes, which is 1,152,921,504,606,846,976 bytes, or 1,024 pebibytes. NIST's page on binary prefixes lists it as the largest of the six original binary multiples.

The decimal exabyte is 10^18 bytes, so the exbibyte is about 15.3 percent larger. A useful landmark is the address space of a 64-bit machine, which can in principle reach 2^64 distinct byte addresses, or 16 exbibytes, a figure that has no neat decimal equivalent.

Real systems seldom approach this size, so the unit appears mostly in discussions of addressing and capacity limits. Like the other IEC names, it states plainly that the count is binary.

1 exbibyte = 1.152921505×10¹⁸ bytes (approximately).

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

Related conversions

See all digital storage units.