Megabytes to Kilobits (MB to kb)

1 megabyte equals 8,000 kilobits exactly.

1 megabyte = 8,000 kilobits

How to convert megabytes to kilobits

To convert megabytes to kilobits, multiply the number of megabytes by 8,000. This factor is exact. To go the other way, multiply kilobits by 0.000125.

kilobits = megabytes × 8,000

Example: 10 megabytes = 80,000 kilobits.

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

Kilobit (kb)

ComputingCurrent unit

1,000 bits (125 bytes). Used for data rates and sizes in telecommunications.

Kilobit means a thousand bits, and in telecommunications data rates are usually measured in decimal SI multiples. The article on the bit gives a handy example: a channel capacity of 8 kbit/s is 1 kB/s, so dividing kilobits by eight gives kilobytes. The binary counterpart, the kibibit, is 1,024 bits, but it is seldom used.

Symbols cause trouble. The IEC standard says to write kbit, while IEEE 1541-2002 recommends a lowercase b, giving kb, and the lowercase b may be confused with capital B for byte. On this site a kilobit is 125 bytes. The history behind it is that of the bit itself: Ralph Hartley proposed a logarithmic information measure in 1928, and Claude Shannon first used the word in 1948, crediting John W. Tukey.

1 kilobit = 125 bytes (exactly).

Sources: Wikipedia: Bit; Wikipedia: Kilobit

Related conversions

See all digital storage units.