Megabytes to Kibibytes (MB to KiB)

1 megabyte equals 976.5625 kibibytes exactly.

How to convert megabytes to kibibytes

To convert megabytes to kibibytes, multiply the number of megabytes by 976.5625. This factor is exact. To go the other way, multiply kibibytes by 0.001024.

kibibytes = megabytes × 976.5625

Example: 10 megabytes = 9,765.625 kibibytes.

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

Megabyte (MB)

ComputingCurrent unit

1,000,000 bytes (decimal). A typical MP3 song is 3–5 MB; a smartphone photo is 2–5 MB.

Megabyte started out as informal jargon. Base-1,024 usage grew because 1,024 is close to 1,000 and convenient for binary multiples. In 1999 the IEC standardized binary prefixes, assigning megabyte to 10 to the sixth bytes and mebibyte to 2 to the twentieth. By the end of 2009 the IEEE, the EU, ISO and NIST had adopted that standard, though the word still carries different meanings in practice.

The famous 1.44 MB floppy disk is a mixed case: it counts 1,024,000 bytes per megabyte, and it actually holds 1,474,560 bytes. Today most storage media and networking use the decimal definition, while Windows uses the binary one for memory such as RAM. For scale, a PlayStation 2 memory card held 8 MB, the plain text of Moby Dick runs to 1.192 MB, and one megabyte holds about one minute of 128 kbit/s MP3 audio.

1 megabyte = 1,000,000 bytes (exactly).

Sources: Wikipedia: Megabyte; NIST: Prefixes for binary multiples

Kibibyte (KiB)

ComputingCurrent unit

Exactly 1,024 bytes (2¹⁰). The IEC name for the binary kilobyte, used by operating systems and memory specifications.

Kibibyte is the first of the names the IEC approved in December 1998 for binary multiples, built from kilobinary. The IUPAC's Interdivisional Committee on Nomenclature and Symbols had proposed binary prefixes in 1995, and the IEC published them in January 1999. The symbol KiB adds an i to the SI symbol, with the K capitalized. NIST says the names keep the first two letters of each SI prefix and add bi, to signal binary.

One KiB is exactly 1,024 bytes, about 2.4 percent more than a kilobyte. The standard is now IEC 80000-13, supported by the BIPM, IEC and NIST. In practice the symbols are rarely used outside a few places such as KDE and Qt-based applications, which can switch between SI and binary units. Donald Knuth jokingly suggested in 1999 calling it a large kilobyte, KKB.

1 kibibyte = 1,024 bytes (exactly).

Sources: NIST: Prefixes for binary multiples; Wikipedia: Kibibyte

Related conversions

See all digital storage units.