Conversion: bits and bytes

1 byte are 8 bits or 1 B = 8 b

Enter the known value in the appropriate line.
The other boxes will show the conversions.
You don't need a calculate bar.

 bits (b) bytes (B) kibibytes (KiB) mebibytes (MiB) gibibytes (GiB) tebibytes (TiB)
 In January 1999, the International Electrotechnical Commission introduced in an addendum to IEC 60027-2 the prefixes kibi- (kibibyte), mebi-, gibi-, etc., and the symbols Ki, Mi, Gi, etc. to specify binary multiples of a quantity and eliminate the ambiguity with their SI meanings. Kibibit sounds a bit funny. Here is the new standard, but hardly anybody is using it:

 Name Symbol Before 1998 standardization Name After the standardization bit b 1 bit = 1 bit bit 1 b = 1 bit byte B 1 B = 8 bit byte 1 B = 8 bit kilobit kbit / kb 1 kbit = 1024 b = bit kilobit 1 kb = 1000 b kibibit Kibit kibibit 1 Kib = 1024 b kilobyte kB 1 kB = 1024 B = Byte kilobyte 1 kB = 1000 B kibibyte KiB kibibyte 1 KiB = 1024 B megabit Mbit 1 Mbit = 1024 kb megabit 1 Mb = 1000 kb mebibit Mibit / Mib mebibit 1 Mib = 1024 Kib megabyte MB 1 MB = 1024 kB megabyte 1 MB = 1000 kB mebibyte Mibit / MiB mebibyte 1 MiB = 1024 KiB gigabit Gbit / Gb 1 Gbit = 1024 Mb gigabit 1 Gb = 1000 MB gibibit Gibit / Gib gibibit 1 Gib = 1024 MiB gigabyte GB 1 GB = 1024 MB gigabyte 1 GB = 1000 MB gibibyte GiB gibibyte 1 GiB = 1024 MiB terabyte TB 1 TB = 1024 GB terabyte 1 TB = 1000 GB tebibyte TiB tebibyte 1 TiB = 1024 GiB petabyte PB 1 PB = 1024 TB petabyte 1 PB = 1000 TB pebibyte PiB pebibyte 1 PiB = 1024 TiB exabyte EB 1 EB = 1024 PB exabyte 1 EB = 1000 PB exbibyte EiB exbibyte 1 EiB = 1024 PiB zettabyte ZB 1 ZB = 1024 EB zettabyte 1 ZB = 1000 EB zebibyte ZiB zebibyte 1 ZiB = 1024 EiB yottabyte YB 1 YB = 1024 ZB yottabyte 1 YB = 1000 ZB yobibyte YiB yobibyte 1 YiB = 1024 ZiB

1 Kibibyte [KiB] = 1024 = 210 Byte
1 Mebibyte [MiB] = 1 048 576 = 220 Byte
1 Gibibyte [GiB] = 1 073 741 824 = 230 Byte
1 Tebibyte [TiB] = 1 099 511 627 776 = 240 Byte
1 Pebibyte [PiB] = 1 125 899 906 842 624 = 250 Byte
1 Exbibyte [EiB] = 1 152 921 504 606 846 976 = 260 Byte
1 Zebibyte [ZiB] = 1 180 591 620 717 411 303 424 = 270 Byte
1 Yobibyte [YiB] = 1 208 925 819 614 629 174 706 176 = 280 Byte
1 Nobibyte [NiB] = 1 237 940 039 285 380 274 899 124 224 = 290 Byte
1 Dobibyte [DiB] = 1 267 650 600 228 229 401 496 703 205 376 = 2100 Byte

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

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 Power Factor kilobinary kibi Ki (210)1 1 024 megabinary mebi Mi (210)2 1 048 576 gigabinary gibi Gi (210)3 1 073 741 824 terabinary tebi Ti (210)4 1 099 511 627 776 petabinary pebi Pi (210)5 1 125 899 906 842 624 exabinary exbi Ei (210)6 1 152 921 504 606 846 976

 Name Prefix Symbol Power Factor kilo kilo k 103 1 000 mega mega M 106 1 000 000 giga giga G 109 1 000 000 000 tera tera T 1012 1 000 000 000 000 peta peta P 1015 1 000 000 000 000 000 exa exa E 1018 1 000 000 000 000 000 000

It is suggested that in English, the first syllable of the name of the binary-multiple prefix should be pronounced in the same way as the first syllable of the name of the corresponding SI prefix, and that the second syllable should be pronounced as "bee." Examples and comparisons with SI prefixes:
1 Kib = 210 bit = 1024 bit,
1 kb = 103 bit = 1000 bit,
1 MiB = 220 B = 1 048 576 B,
1 MB = 106 B = 1 000 000 B,
1 GiB = 230 B = 1 073 741 824 B,
1 GB = 109 B = 1 000 000 000 B.
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 b
1 kilo binary bit = 1 kibibit = 1 Kib = 210 bits = 1 024 b
1 mega byte = 1 MB = 106 Bytes = 1 000 000 B
1 mega binary byte = 1 mebibyte = 1 MiB = (210)2 B = 1 048 576 B

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.

Conversion: Transfer rates and bandwidths
byte = the well-established information measure unity
bit = the well-established data transfer unity
1 kilobit = 1 000 bits

1 megabit = 1 000 000 bits

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

Conclusion: A 56 k modem = 56 000 bits needs for transferring of
56 k data = 458 753 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 data / seconds = transfer rate.

 Connection Theoretical rate in kb Optimal rate in kB Probable rate in kB 14.4 modem 14.4 kb/s 1.2 kB/s 1 kB/s 28.8 modem 28.8 kb/s 2.4 kB/s 2 kB/s 33.6 modem 33.6 kb/s 3 kB/s 2.5 kB/s 56 k  modem 53 kb/s 4.8 kB/s 4 kB/s Single ISDN 64 kb/s 6 kB/s 5 kB/s Dual ISDN 128 kb/s 12 kB/s 10 kB/s DSL - light 384 kb/s 35 kB/s 30 kB/s DSL 1024 kb/s 125 kB/s 90 kB/s DSL 2048 kb/s 250 kB/s 180 kB/s DSL 3072 kb/s 500 kB/s 360 kB/s T1 1.54 Mb/s 150 kB/s 50 kB/s Cable modem 6 Mb/s 768 kB/s 615 kB/s Intranet/LAN 10 Mb/s 1280 kB/s 1024 kB/s 100base-TLAN 100 Mb/s 12800 kB/s 10240 kB/s

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

 In data communications the metric definition of a kilobyte (1000 bytes per kilobyte) is correct. The binary definition of a kilobyte (1024 bytes per kilobyte) is used in areas such as data storage (harddisk, memory), but not for expressing bandwidth and throughput.

 File Storage Capacity by Bits and Bytes bit byte kibibyte mebibyte gibibyte 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 kibibyte 8 192 1 024 1 0.0009765625 9.53674316×10-7 mebibyte 8 388 608 1 048 576 1 024 1 0.0009765625 gibibyte 8 589 934 592 1 073 741 824 1 048 576 1 024 1 tebibyte 8 796 093 022 208 1 099 511 627 776 1 073 741 824 1 048 576 1 024 pebibyte 9 007 199 254 740 990 1 125 899 906 842 624 1 099 511 627 776 1 073 741 824 1 048 576 exbibyte 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 zebibyte 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 × 44 100 × 16 = 1.4112 Mb/s : 8 b/B = 176.4 kb/s
2 × 44 100 × 20 = 1.764 Mb/s : 8 b/B = 220.5 kb/s
2 × 44 100 × 24 = 2.1168 Mb/s : 8 b/B = 264.6 kb/s
2 × 48 000 × 24 = 2.304 Mb/s : 8 b/B = 288.0 kb/s

These words are generally not totally 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 260 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 1

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