I did not make this page, I took it from http://www.chemtutor.com/prex.htm and adapted it to fit into my site.
-Yaron Bandell.
| prefix | symbol | value | value | 'puter jargon usage | origin / plausible alternative |
| deca- | da | 101 | 101 | [3], used to be "deka" | Gk. ten "deka" |
| hecto- | h | 102 | 102 | [3] | Gk. hundred "hekaton" |
| kilo- | k | 10001 | 103 | note lower case "k" | Gk. thousand "chylioi" |
| myria- | ma, my | 104 | 104 | [3], [4] | Gk. ten thousand "myrias" |
| hectokilo- | hk | 105 | 105 | [4] | |
| mega- | M | 10002 | 106 | Gk. large, great "megas" | |
| giga- | G | 10003 | 109 | Gk. giant "gigas" | |
| tera- | T | 10004 | 1012 | Gk. monster "teras" / Gk. four "tetra" | |
| peta- | P | 10005 | 1015 | Gk. five "penta" / Gk. spread "petalos" | |
| exa- | E | 10006 | 1018 | Gk. six hexa" / Gk. outside "exo" | |
| zetta- | Z | 10007 | 1021 | L. ultimate letter z "zeta" | |
| yotta- | Y | 10008 | 1024 | L. penultimate letter y "iota" | |
| harpi- hella- | Hr ?? | 10009 | 1027 | [1], [6] | Marx Bros. Harpo. Austin Sendek is petitioning the International System of Units for 'hella-' |
| grouchi- | Gc | 100010 | 1030 | [1] | Marx Bros. Groucho |
| zeppi- | Zp | 100011 | 1033 | [2] | Marx Bros. Zeppo |
| gummi- | Gm | 100012 | 1036 | [2] | Marx Bros. Gummo |
| chici- | Ch | 100013 | 1039 | [2] | Marx Bros. Chico |
| prefix | symb | value | value | computer jargon usage | origin / plausible alternative |
| deci- | d | 10-1 | 10-1 | [3] | L. tenth "decimus" |
| centi- | c | 10-2 | 10-2 | [3] | L. hundred, hundredth "centum" |
| milli- | m | 1000-1 | 10-3 | seldom used in jargon | L. thousand "mille" |
| decimilli- | dm | 10-4 | 10-4 | [4] | |
| centimilli- | cm | 10-5 | 10-5 | [4] | |
| micro- | µ, u | 1000-2 | 10-6 | [5] small or human-scale | L. small "mikros" |
| nano- | n | 1000-3 | 10-9 | even smaller, used for RAM speed | Gk. dwarf "nanos" |
| pico- | p | 1000-4 | 10-12 | even smaller yet | It. tiny "piccolo" |
| femto- | f | 1000-5 | 10-15 | not used in jargon - yet | O.N. fifteen "femten" |
| atto- | a | 1000-6 | 10-18 | not used in jargon - yet | O.N. eighteen "atten" |
| zepto- | z | 1000-7 | 10-21 | not used in jargon - yet | L. ultimate letter z "zeta" |
| yocto- | y | 1000-8 | 10-24 | not used in jargon - yet | L. penultimate letter y "iota" |
| harpo- | hr | 1000-9 | 10-27 | [1] | Marx Bros. Harpo |
| groucho- | gc | 1000-10 | 10-30 | [1] | Marx Bros. Groucho |
| zeppo- | zp | 1000-11 | 10-33 | [2] | Marx Bros. Zeppo |
| gummo- | gm | 1000-12 | 10-36 | [2] | Marx Bros. Gummo |
| chico- | ch | 1000-13 | 1039 | [2] | Marx Bros. Chico |
| prefix | symb | value | value | origin / plausible alternative | |
| kilo- | K | 10241 | 210 | 1,024 | binary usage, common in computer science |
| kibi- | Ki | 10241 | 210 | 1,024 | IEEE proposal |
| mebi- | Mi | 10242 | 220 | 1,048,576 | IEEE proposal |
| gibi- | Gi | 10243 | 230 | 1,073,741,824 | IEEE proposal |
| tebi- | Ti | 10244 | 240 | 1,099,511,627,776 | IEEE proposal |
| pebi- | Pi | 10245 | 250 | 1,125,899,906,842,624 | IEEE proposal, by extension |
| exbi- | Ei | 10246 | 260 | 1,152,921,504,606,846,976 | IEEE proposal, by extension |
| zebi | Zi | 10247 | 270 | 1,180,591,620,717,411,303,424 | IEEE proposal, by extension |
| yobi- | Yi | 10248 | 280 | 1,208,925,819,614,629,174,706,176 | IEEE proposal, by extension |
| [1] Not SI approved, Morgan Burke [1993] extension, Usenet approved. | |
| [2] Not SI approved, Jargon extension of the Burke extension. | |
| [3] Not SI approved, but in some common usage. | |
| [4] Rarely used, not SI approved. Elicits head-scratching and laughs. | |
| [5] The Greek mu µ is the highly preferred prefix. | |
| [6] Not SI approved, in 2010, UC Davis physics student Austin Sendek started a petition to use 'hella-' for 1027 (instead of 'harpi-'). | |
| NOTE regarding the status of the IEEE proposal: the Comite Consultatif des Unites decided 1995/1996 not to pursue the mebibyte and related units further at that time. |
| attoparsec (approximately = 3.1cm) | |
| microfortnight (= 1.2096 sec) |