### DIGITAL INFORMATIONBIT and BYTE CONVERSION CALCULATOR

 Decimal (SI prefixes) Binary (SI prefixes) Binary IEC bit b bit b bit b byte B byte B byte B kilobit kbkbit kilobit KbKbit kibibit Kibit kilobyte kB kilobyte KB kibibyte KiB megabit MbMbit megabit MbMbit mebibit Mibit megabyte MB megabyte MB mebibyte MiB gigabit GbGbit gigabit GbGbit gibibit Gibit gigabyte GB gigabyte GB gibibyte GiB terabit TbTbit terabit TbTbit tebibit Tibit terabyte TB terabyte TB tebibyte TiB petabit PbPbit petabit PbPbit pebibit Pibit petabyte PB petabyte PB pebibyte PiB exabit EbEbit exabit EbEbit exbibit Eibit exabyte EB exabyte EB exbibyte EiB zettabit ZbZbit zettabit ZbZbit zebibit Zibit zettabyte ZB zettabyte ZB zebibyte ZiB yottabit YbYbit yottabit YbYbit yobibit Ybit yottabyte YB yottabyte YB yobibyte YiB

## Units of Digital Information in Computing and Telecommunications

Definition:

### bit (bit, b)

A bit is the basic unit of information in computing and telecommunications; it is the amount of information that can be stored by a device and can normally exist in only two distinct states. A bit can also be defined as a variable or computed quantity that can have only two possible values. These two values are often interpreted as binary digits and are usually denoted by digits 0 and 1. ISO/IEC IEC 80000-13:2008 specifies that the symbol for bit should be "bit", though the letter "b" (in lower case) is still widely used.

### byte (B) also octet(o)

A byte or octet is a unit of memory or data equal to the amount used to represent one character; The size of a byte is typically hardware dependent, but the modern de facto standard is 8 bits. However, byte has been used for numbers of bits other than 8. To avoid the risk of confusion ISO/IEC IEC 80000-13:2008 strongly recommends that the name byte and the symbol "B" (capital letter) be used only for 8-bit bytes. A computer with 8-bit bytes can distinguish 28 = 256 different characters. The symbol "B" is not international and should not be confused with the symbol "B" for bel

Prefixes for binary multiples
Computers use bits (binary digit), which are composed of ones and zeros. The decimal number system in contrast has ten unique digits, zero through nine. But although computer data and file size is normally measured using the binary number system (counted by factors of two 1, 2, 4, 8, 16, 32, 64, etc), the prefixes for the multiples were based on the metric/SI system because computer industry noticed that 210 was very nearly equal to 1000 and started using the SI prefix "kilo" to mean 1024! So, although a metric/SI "kilo" equals 1,000 (e.g. one kilogram = 1,000 grams), a binary "Kilo" equals 1,024 (e.g. one Kilobyte = 1,024 bytes). Not surprisingly leading to confusion, particularly when many storage device manufacturers and telecommunications engineers use the decimal prefixes. So a "500 GB hard drive" may show only 465 GB (500,000,000,000 bytes) on the computer. No Surprise, some may feel they have been cheated out of 35 GB. A big potential for confusion and for incompatibility in standards and in implemented systems exists.

In December 1998, the International Electrotechnical Commission (IEC) approved a new standard. Instead of using the metric prefixes for multiples in binary code, the new IEC standard called for specific prefixes for binary multiples made up of only the first two letters of the metric prefixes and adding the first two letters of the word "binary". Instead of Kilobyte (KB) or Gigabyte (GB), the new terms would be kibibyte (KiB) or gibibyte (GiB).

Summary

The common use of metric/SI prefixes for binary multiples can lead to confusion over whether value is binary or decimal. Use of "k" for decimal kilo and "K" for binary helps but not with other prefixes like mega (M) and giga (G). Symbol b for bit and B for byte is used to differentiate, but is still subject to confusion.

kb - kilobit - 1000 (103) bits
Kb - kilobit - 1024 (210) bits
kB - kilobyte - 1000 (103) bytes
KB - Kilobyte - 1024 (210) bytes
Mb - megabit - 1000000 (106) or 1048576 (220) bits
MB - megabyte - 1000000 (106) or 1048576 (220) bytes

New IEC standard should make things clearer. Confusion may still exist with use of old and new metric/SI prefixes.

KiB - kibibyte - 1024 (210) bytes
MB - megabyte - 1000000 (106) bytes. (SI prefix for decimal use only - may cause confusion with old system).

SymbolPrefixSIBinarySize difference
kkilo103   = 10001210 = 102412.40%
Mmega106   = 10002220 = 102424.86%
Ggiga109   = 10003230 = 102437.37%
Ttera1012 = 10004240 = 102449.95%
Ppeta1015 = 10005250 = 1024512.59%
Eexa1018 = 10006260 = 1024615.29%
Zzetta1021 = 10007270 = 1024718.67%
Yyotta1024 = 10008280 = 1024820.89%

SymbolPrefix
Kikibi, binary kilokibibyte (KiB)210 bytes1024 B
Mimebi, binary megamebibyte (MiB)220 bytes1024 KiB
Gigibi, binary gigagibibyte (GiB)230 bytes1024 MiB
Titebi, binary teratebibyte (TiB)240 bytes1024 GiB
Pipebi, binary petapebibyte (PiB)250 bytes1024 TiB
Eiexbi, binary exaexbibyte (EiB)260 bytes1024 PiB
Zizebi, binary zettazebibyte (ZiB)270 bytes1024 EiB
Yiyobi, binary yottayobibyte (EiB)280 bytes1024 ZiB

Data Transfer Rate - bits per second and bytes per second are confusing to those outside the specific industries. Terms such as 56K, 56 kb/s, 56Kb/s, 56 kbps, 56 Kbps, 56 kBps, 56 KBps etc. don't help. In most cases bitrate prefixes are used in the decimal sense.

### CONVERSION CALCULATORS

#### Convert between Different Units of Measurement

 Index of Unit Converters

To use the measurement conversion calculators simply enter a number value into the desired field and click calculate. All results shown will be equivalent values. Values are given to seven significant figures ( the odd result may show 9's or 0's over running). Values of 10 000 or greater will be displayed in the e-format e.g. 2.3456e7 which equals 2.3456 x 107 or 23 456 000. Values lower than 0.001 will be displayed in the e-format e.g. 2.3456e-5 which equals 2.3456 x 10-5 or 0.000 023456. The calculators require that your browser has java script enabled. View all measurement unit conversion calculators on the same page (may not work with all browsers; requires Iframe).

Si Units:

Custom Search

Telephone: +44 (0)1252 405186

Thermal Spray Processes:

Combustion Wire Thermal Spray Process

Combustion Powder Thermal Spray Process

Arc Wire Thermal Spray Process

Plasma Thermal Spray Process

HVOF Thermal Spray Process

Detonation Thermal Spray Process

Plasma Flame Theory

Cold Spray Coating Process

Wear and Use of Thermal Spray Coatings

Corrosion and Use of Thermal Spray Coatings

Glossary of Thermal Spray and Surface Engineering Terms

Image Directory for Thermal Spray Coatings

Plasma Gas Flow Information

Plasma Gas Flow Correction Calculator

Contact Form

Links to other interesting sites related to thermal spray and surface engineering

Periodic Table of the Elements

SI Units

Calculators for Conversion between Units of Measurement

Hardness Testing

Surface Engineering Message Board Archive

Surface Engineering Message Board Archive Index

Search This Site

Photography Gallery2

Photography Gallery3