An order of magnitude is generally a factor of ten. A quantity growing by four orders of magnitude implies it has grown by a factor of 10000 or 104. However, because computers are binary, orders of magnitude are sometimes given as powers of two.
This article presents a list of multiples, sorted by orders of magnitude, for digital information storage measured in bits. This article assumes a descriptive attitude towards terminology, reflecting general usage. The article assumes the following:
- A group of 8 bits constitutes one byte. The byte is the most common unit of measurement of information (megabyte, mebibyte, gigabyte, gibibyte, etc.).
- In 16-bit and 32-bit architectures, having processor registers of these sizes, that chunk of data is usually called a word.
- The decimal SI prefixes kilo, mega etc., are powers of 10. The power of two equivalents are the binary prefixes kibi, mebi, etc.
Accordingly:
- 1 kB (kilobyte) = 1000 bytes = 8000 bits
- 1 KiB (kibibyte) = 210 bytes = 1024 bytes = 8192 bits
Binary | Decimal | Item | ||
---|---|---|---|---|
Factor | Term | Factor | Term | |
20 | bit | 100 | bit | 1 bit – 0 or 1, false or true, Low or High |
1.6 bits – approximate size of a trit (a base-3 digit) | ||||
21 | 2 bits – a crumb (rarely used term), enough to uniquely identify one base pair of genetic code | |||
3 bits – the size of an octal digit | ||||
22 | nibble | 4 bits – (aka "nibble" or "semioctet", rarely used) the size of a hexadecimal digit; decimal digits in binary-coded decimal form | ||
5 bits – the size of code points in the Baudot code, used in telex communication | ||||
6 bits – the size of code points in Univac Fieldata, in IBM "BCD" format, and in Braille. Enough to uniquely identify one codon of genetic code. | ||||
7 bits – the size of code points in the ASCII character set
– minimum length to store 2 decimal digits |
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23 | byte | 8 bits – (a.k.a. "octet") on many computer architectures.
– Equivalent to 1 "word" on 8-bit computers (Apple II, Atari 800, Commodore 64, et al.). |
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101 | decabit | 10 bits – minimum bit length to store a single byte with error-correcting memory |
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12 bits – wordlength of the PDP-8 of Digital Equipment Corporation (built from 1965–1990) | ||||
24 | 16 bits – commonly used in many programming languages, the size of an integer capable of holding 65,536 different values |
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25 | 32 bits (4 bytes) – size of an integer capable of holding 4,294,967,296 different values |
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36 bits – size of word on Univac 1100-series computers and Digital Equipment Corporation's PDP-10 | ||||
56 bits (7 bytes) – cipher strength of the DES encryption standard | ||||
26 | 64 bits (8 bytes) – size of an integer capable of holding 18,446,744,073,709,551,616 different values |
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80 bits (10 bytes) – size of an extended precision floating point number, for intermediate calculations that can be performed in floating point units of most processors of the x86 family | ||||
102 | hectobit | 100 bits | ||
27 | 128 bits (16 bytes) – size of addresses in IPv6, the successor protocol of IPv4 |
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160 bits – maximum key length of the SHA-1, standard Tiger (hash), and Tiger2 cryptographic message digest algorithms | ||||
28 | 256 bits (32 bytes) – minimum key length for the recommended strong cryptographic message digests as of 2004 | |||
29 | 512 bits (64 bytes) – maximum key length for the standard strong cryptographic message digests in 2004 | |||
103 | kilobit | 1000 bits | ||
210 | kibibit | 1024 bits (128 bytes) | ||
1288 bits – approximate maximum capacity of a standard magnetic stripe card | ||||
211 | 2048 bits (256 bytes) – RAM capacity of the stock Altair 8800 | |||
212 | 4096 bits (512 bytes)
– typical sector size, and minimum space allocation unit on computer storage volumes, with most file systems |
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4704 bits (588 bytes) – uncompressed single-channel frame length in standard MPEG audio (75 frames per second and per channel), with medium quality 8-bit sampling at 44,100 Hz (or 16-bit sampling at 22,050 Hz) | ||||
8000 bits (103 bytes) – one kilobyte | ||||
213 | kibibyte | 8192 bits (1,024 bytes) – RAM capacity of a Sinclair ZX81. | ||
9408 bits (1,176 bytes) – uncompressed single-channel frame length in standard MPEG audio (75 frames per second and per channel), with standard 16-bit sampling at 44,100 Hz | ||||
104 | 15,360 bits – one screen of data displayed on an 8-bit monochrome text console (80x24) | |||
214 | 16,384 bits (2 kibibytes) – one page of typed text, RAM capacity of Nintendo Entertainment System | |||
215 | 32,768 bits (4 kibibytes) | |||
216 | 65,536 bits (8 kibibytes) | |||
105 | 100,000 bits | |||
217 | 131,072 bits (16 kibibytes) – RAM capacity of the smallest Sinclair ZX Spectrum. | |||
160 kilobits – approximate size of this article as of 15 April 2010 | ||||
218 | 262,144 bits (32 kibibytes) | |||
219 | 524,288 bits (64 kibibytes) – RAM capacity of a lot of popular 8-bit Computers like the C-64, Amstrad CPC etc. | |||
106 | megabit | 1,000,000 bits | ||
220 | mebibit | 1,048,576 bits (128 kibibytes) – RAM capacity of popular 8-bit Computers like the C-128, Amstrad CPC etc. | ||
1,978,560 bits – a one-page, standard-resolution black-and-white fax (1728 × 1145 pixels) | ||||
221 | 2,097,152 bits (256 kibibytes) | |||
4,147,200 bits – one frame of uncompressed NTSC DVD video (720 × 480 × 12 bpp Y'CbCr) | ||||
222 | 4,194,304 bits (512 kibibytes) | |||
4,976,640 bits – one frame of uncompressed PAL DVD video (720 × 576 × 12 bpp Y'CbCr) | ||||
5,242,880 bits (640 kibibytes) – the maximum addressable memory of the original IBM PC architecture | ||||
8,000,000 bits (106 bytes) – the preferred definition of megabyte | ||||
8,343,400 bits – one "typical" sized photograph with reasonably good quality (1024 × 768 pixels). | ||||
223 | mebibyte | 8,388,608 bits (1024 kibibytes), one of a few traditional meanings of megabyte | ||
107 | 11,520,000 bits – capacity of a lower-resolution computer monitor (as of 2006), 800 × 600 pixels, 24 bpp | |||
11,796,480 bits – capacity of a 3.5 in floppy disk, colloquially known as 1.44 megabyte but actually 1.44 × 1000 × 1024 bytes | ||||
224 | 16,777,216 bits (2 mebibytes) | |||
25 megabits – amount of data in a typical color slide | ||||
225 | 33,554,432 bits (4 mebibytes) – RAM capacity of stock Nintendo 64 | |||
41,943,040 bits (5 mebibytes) – approximate size of the Complete Works of Shakespeare | ||||
98,304,000 bits – capacity of a high-resolution computer monitor as of 2011, 2560 × 1600 pixels, 24 bpp | ||||
50–100 megabits – amount of information in a typical phone book | ||||
226 | 108 | 67,108,864 bit (8 mebibytes) | ||
227 | 134,217,728 bits (16 mebibytes) | |||
150 megabits – amount of data in a large foldout map | ||||
228 | 268,435,456 (32 mebibytes) | |||
423,360,000 bits: a five-minute audio recording, in CDDA quality | ||||
229 | 536,870,912 bits (64 mebibytes) | |||
109 | gigabit | 1,000,000,000 bits | ||
230 | gibibit | 1,073,741,824 bits (128 mebibytes) | ||
231 | 2,147,483,648 bits (256 mebibytes) | |||
232 | 4,294,967,296 bits (512 mebibytes) | |||
5.45×109 bits (650 mebibytes) – capacity of a regular compact disc | ||||
5.89×109 bits (702 mebibytes) – capacity of a large regular compact disc | ||||
6.4×109 bits – capacity of the human genome (assuming 2 bits for each base pair) | ||||
233 | gibibyte | 8,589,934,592 bits (1024 mebibytes) | ||
1010 | 10,000,000,000 bits | |||
234 | 17,179,869,184 bits (2 gibibytes) | |||
235 | 34,359,738,368 bits (4 gibibytes) – maximum addressable memory on the Intel 80386 | |||
3.76×1010 bits (4.7 gigabytes) – capacity of a single-layer, single-sided DVD | ||||
236 | 68,719,476,736 bits (8 gibibytes) | |||
1011 | 100,000,000,000 bits | |||
237 | 137,438,953,472 bits (16 gibibytes) | |||
1.46×1011 bits (17 gigabytes) – capacity of a double-sided, dual-layered DVD | ||||
2.15×1011 bits (25 gigabytes) – capacity of a single-sided, single-layered 12-cm Blu-ray disc | ||||
238 | 274,877,906,944 bits (32 gibibytes) | |||
239 | 549,755,813,888 bits (64 gibibytes) | |||
1012 | terabit | 1,000,000,000,000 bits (125 gigabytes) | ||
240 | tebibit | 1.34×1012 bits – estimated capacity of the Polychaos dubium genome, the largest known genome | ||
1.6×1012 bits (200 gigabytes) – capacity of a hard disk that would be considered average as of 2008 | ||||
241 | 2,199,023,255,552 bits (256 gibibytes) | |||
242 | 4,398,046,511,104 bits (512 gibibytes) | |||
243 | tebibyte | 8,796,093,022,208 bits (1024 gibibytes) | ||
(approximately) 8.97×1012 bits – as of 2010, data of π to the largest number of decimal digits ever calculated (2.7×1012) | ||||
1013 | 10,000,000,000,000 bits (1.25 terabytes) – capacity of a human being's functional memory, according to Raymond Kurzweil in The Singularity Is Near, p. 126 | |||
244 | 17,592,186,044,416 bits (2 tebibytes) | |||
245 | 35,184,372,088,832 bits (4 tebibytes) | |||
246 | 70,368,744,177,664 bits (8 tebibytes) | |||
1014 | 100,000,000,000,000 bits | |||
247 | 140,737,488,355,328 bits (16 tebibytes) | |||
1.5×1014 bits (18.75 terabytes) | ||||
248 | 281,474,976,710,656 bits (32 tebibytes) | |||
249 | 562,949,953,421,312 bits (64 tebibytes) | |||
1015 | petabit | 1,000,000,000,000,000 bits | ||
250 | pebibit | 1,125,899,906,842,624 bits (128 tebibytes) | ||
2.4×1015 bits (300 terabytes) – size of the Internet Archive as of 2004 | ||||
251 | 2,251,799,813,685,248 bits (256 tebibytes) | |||
252 | 4,503,599,627,370,496 bits (512 tebibytes) | |||
8,000,000,000,000,000 bits (1015 bytes) – one petabyte | ||||
253 | pebibyte | 9,007,199,254,740,992 bits (1024 tebibytes) | ||
1016 | 10,000,000,000,000,000 bits | |||
254 | 18,014,398,509,481,984 bits (2 pebibytes) | |||
255 | 36,028,797,018,963,968 bits (4 pebibytes) – theoretical maximum of addressable physical memory in the AMD64 architecture | |||
4.5×1016 bits (5.625 petabytes) – estimated hard drive space in Google's server farm as of 2004 | ||||
256 | 72,057,594,037,927,936 bits (8 pebibytes) | |||
10 petabytes (1016 bytes) – estimated approximate size of the Library of Congress's collection, including non-book materials, as of 2005 | ||||
1017 | 100,000,000,000,000,000 bits | |||
257 | 144,115,188,075,855,872 bits (16 pebibytes) | |||
2×1017 bits (25 petabytes) – Storage space of Megaupload file-hosting service at the time it was shut down in 2012 | ||||
258 | 288,230,376,151,711,744 bits (32 pebibytes) | |||
259 | 576,460,752,303,423,488 bits (64 pebibytes) | |||
8 ×1017, the storage capacity of the fictional Star Trek character Data | ||||
1018 | exabit | 1,000,000,000,000,000,000 bits | ||
260 | exbibit | 1,152,921,504,606,846,976 bits (128 pebibytes) | ||
1.6×1018 bits (200 petabytes) – total amount of printed material in the world | ||||
261 | 2,305,843,009,213,693,952 bits (256 pebibytes) | |||
262 | 4,611,686,018,427,387,904 bits (512 pebibytes) | |||
263 | exbibyte | 9,223,372,036,854,775,808 bits (1024 pebibytes) | ||
1019 | 10,000,000,000,000,000,000 bits | |||
264 | 18,446,744,073,709,551,616 bits (2 exbibytes) | |||
265 | 36,893,488,147,419,103,232 bits (4 exbibytes) | |||
50,000,000,000,000,000,000 bits (50 exabit) | ||||
266 | 73,786,976,294,838,206,464 bits (8 exbibytes) | |||
1020 | 100,000,000,000,000,000,000 bits | |||
267 | 147,573,952,589,676,412,928 bits (16 exbibytes) – maximum addressable memory using 64bit addresses without segmentation | |||
268 | 295,147,905,179,352,825,856 bits (32 exbibytes) | |||
3.5 × 1020 bits – increase in information capacity when 1 Joule of energy is added to a heat-bath at 300 K (27 °C) | ||||
269 | 590,295,810,358,705,651,712 bits (64 exbibytes) | |||
1021 | zettabit | 1,000,000,000,000,000,000,000 bits | ||
270 | zebibit | 1,180,591,620,717,411,303,424 bits (128 exbibytes) | ||
271 | 2,361,183,241,434,822,606,848 bits (256 exbibytes) | |||
3.4×1021 bits (0.36 zettabytes) – amount of information that can be stored in 1 gram of DNA | ||||
4.7×1021 bits (0.50 zettabytes) – amount of digitally stored information in the world as of May 2009 | ||||
272 | 4,722,366,482,869,645,213,696 bits (512 exbibytes) | |||
273 | zebibyte | 9,444,732,965,739,290,427,392 bits (1024 exbibytes) | ||
1022 | 10,000,000,000,000,000,000,000 bits | |||
1023 | 1.0×1023 bits – increase in information capacity when 1 Joule of energy is added to a heat-bath at 1 K (−272.15 °C) | |||
6.0×1023 bits – information content of 1 mole (12.01 g) of graphite at 25 °C; equivalent to an average of 0.996 bits per atom. | ||||
1024 | yottabit | 7.3×1024 bits – information content of 1 mole (18.02 g) of liquid water at 25 °C; equivalent to an average of 12.14 bits per molecule. | ||
280 | yobibit | 1,208,925,819,614,629,174,706,176 bits (128 zebibytes) | ||
1025 | 1.1×1025 bits – entropy increase of 1 mole (18.02 g) of water, on vaporizing at 100 °C at standard pressure; equivalent to an average of 18.90 bits per molecule. | |||
1.5×1025 bits – information content of 1 mole (20.18 g) of neon gas at 25 °C and 1 atm; equivalent to an average of 25.39 bits per atom. | ||||
2 150 | 1045 | ~ 1045 bits – the number of bits required to perfectly recreate the average-sized U.S. adult male human being down to the quantum level on a computer is about 2×1045 bits of information (see Bekenstein bound for the basis for this calculation). | ||
1058 | ~ 1058 bits – thermodynamic entropy of the sun (about 30 bits per proton, plus 10 bits per electron). | |||
1069 | ~ 1069 bits – thermodynamic entropy of the Milky Way Galaxy (counting only the stars, not the black holes within the galaxy) | |||
1077 | 1.5×1077 bits – information content of a one-solar-mass black hole. | |||
2305 | 1092 | The information capacity of the observable universe, according to Seth Lloyd. | ||
2332.19 | 10100 | googol number | ||
23.3219·googol | 10googol | googolplex number |
For comparison, the Avogadro constant is 6.02214179(30)×1023 entities per mole, based upon the number of atoms in 12 grams of carbon-12 isotope.
Famous quotes containing the words orders and/or magnitude:
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—Bruno Bettelheim (20th century)
“He all their ammunition
And feats of war defeats
With plain heroic magnitude of mind
And celestial vigour armed;”
—John Milton (16081674)