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:
“What is all wisdom save a collection of platitudes? Take fifty of our current proverbial sayingsthey are so trite, so threadbare, that we can hardly bring our lips to utter them. None the less they embody the concentrated experience of the race and the man who orders his life according to their teaching cannot go far wrong.”
—Norman Douglas (18681952)
“Constancy has nothing virtuous in itself, independently of the pleasure it confers, and partakes of the temporizing spirit of vice in proportion as it endures tamely moral defects of magnitude in the object of its indiscreet choice.”
—Percy Bysshe Shelley (17921822)