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Conversion: bits and bytes

1 byte are 8 bits

Bits (b)
Bytes (B)
Kilobytes (kB)
Megabytes (MB)
Gigabytes (GB)
Terabytes (TB)

We got a new standard. Kibibit sounds very funny and strange.
Will it become widely accepted? Here is it:

Name Symbol Before the standardization After the standardization
bit b 1 bit = 1 bit 1 bit = 1 bit
byte B 1 B = 8 bit 1 B = 8 bit
kilobit kbit / kb 1 kbit = 1024 bit 1 kBit = 1000 bit
Kibibit KiBit         1 KiBit = 1024 bit
kilobyte kB 1 kB = 1024 B = Byte 1 kB = 1000 Byte
kibibyte KiB         1 KiB = 1024 Byte
megabit MBit / Mb 1 MBit = 1024 KBit 1 MBit = 1000 kBit
mebibit MiBit / Mib         1 Mib = 1024 KiBit
megabyte MB 1 MB = 1024 kB 1 MB = 1000 kB
Mebibyte MiBit / MiB         1 MiB = 1024 KiB
gigabit GBit / Gb 1 GBit = 1024 MBit 1 GBit = 1000 MBit
gibibit GiBit / Gib         1 Gib = 1024 MiBit
gigabyte GB 1 GB = 1024 MB 1 GB = 1000 MB
gibibyte GiB         1 GiB = 1024 MiB
terabyte TB 1 TB = 1024 GB 1 TB = 1000 GB
tebibyte TiB         1 TiB = 1024 GiB
petabyte PB 1 PB = 1024 TB 1 PB = 1000 TB
pebibyte PiB         1 PiB = 1024 TiB
exabyte EB 1 EB = 1024 PB 1 EB = 1000 PB
exbibyte EiB         1 EiB = 1024 PiB
zettabyte ZB 1 ZB = 1024 EB 1 ZB = 1000 EB
zebibyte ZiB         1 ZiB = 1024 EiB
yottabyte YB 1 YB = 1024 ZB 1 YB = 1000 ZB
yobibyte YiB         1 YiB = 1024 ZiB

    Old Definitions:
  • 1 kb = (210) bits = 1,024 bits
  • 1 MB = (210)2 Bytes = 1,048,576 Bytes

To make the SI prefixes universal and to avoid confusion in the future, International Electrotechnical Commission (IEC), the leading international organization for worldwide standardization in electrotechnology, approved in December 1998 standard names and symbols of prefixes for binary multiples to be used in the fields of data processing and transmission. The prefixes are:

Name Prefix Symbol Factor
kilobinary kibi Ki 210
megabinary mebi Mi (210)2
gigabinary gibi Gi (210)3
terabinary tebi Ti (210)4
petabinary pebi Pi (210)5
exabinary exbi Ei (210)6

Based on the new definitions, the SI prefixes, k, M, and G, are back to their original meaning of 1,000, 1,000,000, and 1,000,000,000, respectively. The commonly known binary prefixes are written as Ki, Mi, and Gi and pronounced as kibi, mebi, and gibi, respectively. New Definitions:

  • 1 kilo-bit = 1 kb = 103 bits = 1,000 bits
  • 1 kilobinarybit = 1 kibibit = 1 Kib =210 bits = 1,024 bits
    •
  • 1 megabyte = 1 MB = 106 Bytes = 1,000,000 Bytes
    •
  • 1 megabinarybyte = 1 mebibyte = 1 MiB = (210)2 Bytes = 1,048,576 Bytes
    •

    The IEEE Standards Board decided that IEEE standards will be using the conventional, internationally adopted, definitions of the base-ten SI prefixes, except that the base-two definition may be used if such usage is explicitly pointed out on a case-by-case basis.

    Byte = the well-established information measure unity

    1 byte = 8 bits and 1 kilobyte (K / Kb) = 210 bytes = 1,024 bytes
    1 megabyte (M / MB) = 220 = 1,048,576 bytes and 1 gigabyte (G / GB) = 230 bytes = 1,073,741,824 bytes
    1 terabyte (T / TB) = 240 bytes = 1,099,511,627,776 bytes and 1 petabyte (P / PB) = 250 bytes = 1,125,899,906,842,624 bytes
    1 exabyte (E / EB) = 260 bytes = 1,152,921,504,606,846,976 bytes

    bit = the well-established data transfer unity

    1 kilobit = 1000 bits
    1 megabit = 1000000 bits

    Datas of the hard disk are counted in kilobytes, however the transfer data rates are in kilobits.

    Conclusion: A 56 k modem (= 56000 bits) needs for transferring of
    56 k datas (= 458753 bits) not 1 second, but at least 8,2 seconds.
    This is confusing and you must always bear it in mind, when calculating transfer rates.

    Rule of thumb : KByte of the datas / seconds = transfer rate.

    Connection Theoretical
    rate in KBit    		 Optimal
    rate in KByte    		 Probable
    rate in KByte
    14.4 modem 14.4 kbit/s 1.2 KByte/s   1 KByte/s
    28.8 modem 28.8 kbit/s 2.4 KByte/s   2 KByte/s
    33.6 modem 33.6 kbit/s    3 KByte/s 2.5KByte/s
    56 k  modem    53 kbit/s 4.8 KByte/s   4 KByte/s
    Single ISDN    64 kbit/s 6 KByte/s   5 KByte/s
    Dual ISDN 128 kbit/s 12 KByte/s 10 KByte/s
    DSL - light 384 kbit/s 35 KByte/s 30 KByte/s
    DSL 1024 kbit/s 125 KByte/s 90 KByte/s
    DSL 2048 kbit/s 250 KByte/s 180 KByte/s
    DSL 3072 kbit/s 500 KByte/s 360 KByte/s
    T1 1,54 Mbis/s 150 KByte/s 50 Kbyte/s
    Cable modem   6 Mbits/s 300 KByte/s 50 KByte/s
    Intranet / LAN 10 Mbits/s 350 KByte/s 35 KByte/s
    100 base-T Lan 100 Mbits/s 500 KByte/s 50 KByte/s

    The new IEC Standard
    bit bit 0 or 1
    byte B 8 bits
    kibibit Kibit 1024 bits
    kilobit kbit 1000 bits
    kibibyte (binary) KiB 1024 bytes
    kilobyte (decimal) kB 1000 bytes
    megabit Mbit 1000 kilobits
    mebibyte (binary) MiB 1024 kibibytes
    megabyte (decimal) MB 1000 kilobytes
    gigabit Gbit 1000 megabits
    gibibyte (binary) GiB 1024 mebibytes
    gigabyte (decimal) GB 1000 megabytes
    terabit Tbit 1000 gigabits
    tebibyte (binary) TiB 1024 gibibytes
    terabyte (decimal) TB 1000 gigabytes
    petabit Pbit 1000 terabits
    pebibyte (binary) PiB 1024 tebibytes
    petabyte (decimal) PB 1000 terabytes
    exabit Ebit 1000 petabits
    exbibyte (binary) EiB 1024 pebibytes
    exabyte (decimal) EB 1000 petabytes

    File Storage Capacity by Bits and Bytes
      bit byte Kilobyte Megabyte Gigabyte
    bit 1 0.125 0.000122070312 1.192092895 × 10-7 1.16415321875 × 10-10
    byte 8 1 0.0009765625 9.53674316 × 10-7 9.31322575 × 10-10
    Kilobyte 8 192 1 024 1 0.0009765625 9.53674316 × 10-7
    Megabyte 8 388 608 1 048 576 1 024 1 0,0009765625
    Gigabyte 8,589,934,592 1,073,741,824 1,048,576 1,024 1
    Terabyte 8,796,093,022,208 1,099,511,627,776 1,073,741,824 1,048,576 1,024
    Petabyte 9,007,199,254,740,990 1,125,899,906,842,624 1,099,511,627,776 1,073,741,824 1,048,576
    Exabyte 9,223,372,036,854,780,000 1,152,921,504,606,846,976 1,125,899,906,842,624 1,099,511,627,776 1,073,741,824
    Zettabyte 9,444,732,965,739,290,000,000 1,180,591,620,717,411,303,424 1,152,921,504,606,846,976 1,125,899,906,842,624 1,099,511,627,776

    CD: 2 · 44100 · 16 = 1,4112 MBit/s : 8 bit/byte = 176,4 kbyte/s
    2 · 44100 · 20 = 1,764 MBit/s : 8 bit/byte = 220,5 kbyte/s
    2 · 44100 · 24 = 2,1168 MBit/s : 8 bit/byte = 264,6 kbyte/s
    2 · 48000 · 24 = 2,304 MBit/s : 8 bit/byte = 288,0 kbyte/s

    These words are generally not accepted.
    Units from Amendment 2 - International Standard IEC 60027-2

    Prefix Symbol Power Factor
    Yotta Y 1024 1,000,000,000,000,000,000,000,000
    Zetta Z 1021 1,000,000,000,000,000,000,000
    Exbi Ei 250 1,152,921,504,606,846,976
    Exa E 1018 1,000,000,000,000,000,000
    Pebi Pi 250 1,125,899,906,842,624
    Peta P 1015 1,000,000,000,000,000
    Tebi Ti 240 1,099,511,627,776
    Tera T 1012 1,000,000,000,000
    Gibi Gi 230 1,073,741,824
    Giga G 109 1,000,000,000
    Mebi Mi 220 1,048.576
    Mega M 106 1,000,000
    Kibi Ki 210 1,024
    Kilo k 103 1,000
    Reference unit 100 1