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IEC Units (computer units/microsoft units) and SI units

 
IEC Units (Computer/Microsoft units) and International System of Units (SI Units)
IEC Units   SI Units
2X 1024X IEC name value   10X 1000X SI name value
280 10248 Yi Yobi 1,208,925,819,614,629,174,706,176   1024 10008 Y yotta 1,000,000,000,000,000,000,000,000
270 10247 Zi Zebi 1,180,591,620,717,411,303,424   1021 10007 Z zeta 1,000,000,000,000,000,000,000
260 10246 Ei Exbi 1,152,921,504,606,846,976   1018 10006 E exa 1,000,000,000,000,000,000
250 10245 Pi Pebi 1,125,899,906,842,624   1015 10005 P peta 1,000,000,000,000,000
240 10244 Ti Tebi 1,099,511,627,776   1012 10004 T tera 1,000,000,000,000
230 10243 Gi Gibi 1,073,741,824   109 10003 G giga 1,000,000,000
220 10242 Mi Mebi 1,048,576   106 10002 M mega 1,000,000
210 10241 Ki Kibi 1024   103 10001 k kilo 1,000
            102   h hecto 100
            101   da deka 10
20 10240     1   100 10000     1
            10-1   d deci 0.1
            10-2   c centi 0.01
2-10 1024-1 mi mibi .0009765625   10-3 1000-1 m milli 0.001
2-20 1024-2 µi µbi(mubi) 0.00000095367431640625   10-6 1000-2 µ micro 0.000001
2-30 1024-3 ni nabi 0.000000000931322574615478515625   10-9 1000-3 n nano 0.000000001
2-40 1024-4 pi pibi 9.094947017729282379150390625e-13
0.0000000000009094947017729282379150390625
  10-12 1000-4 p pico 0.000000000001
2-50 1024-5 fi fembi 8.8817841970012523233890533447265625e-16
0.00000000000000088817841970012523233890533447265625
  10-15 1000-5 f femto 0.000000000000001
2-60 1024-6 ai abi 8.67361737988403547205962240695953369140625e-19
0.000000000000000000867361737988403547205962240695953369140625
  10-18 1000-6 a atto 0.000000000000000001
2-70 1024-7 zi zebi

8.470329472543003390683225006796419620513916015625e-22
0.0000000000000000000008470329472543003390683225006796419620513916015625

  10-21 1000-7 z zepto 0.000000000000000000001
2-80 1024-8 yi yobi 8.2718061255302767487140869206996285356581211090087890625e-25
0.00000000000000000000000082718061255302767487140869206996285356581211090087890625
  10-24 1000-8 y yocto 0.000000000000000000000001
results calculated using pari/gp. 1024=2^10. document can be printed landscape with margins 0.5". IEC names are formed using the first syllable of the SI name followed by bi (pronounced bee) hinted at by NIST IEC Prefixes Reference.

1GB=1000MB in SI units. SI units: hard disk sizes [everybody wishes they would switch over to IEC...])

1GiB=1024MiB in IEC units. IEC units: SSD, flash drives, RAM sizes, optical disk sizes and optical disk sector sizes, hard disk sector sizes. microsoft, optical disc industry, ssd industry, mislabels GiB as GB, KiB as KB, etc, ram and SSD and flash drives and optical disc industries do the same, just for "ease and simplicity" and "everybody's doing it". yuck. Throw the standards out the window, we are doing defacto. In fact, I don't know of one manufacturing industry that has used the official IEC units. and people are sometimes getting confused as a result. not good. would be nice if pc industry used 1 standard and stuck with it. hard disks are the odd lot: disk size is in SI units, but the sector size is in IEC units (512 bytes, 1KiB, 4KiB) - that causes an awful lot of confusion. it's been that way since hard drives have been around and nobody has changed it (they should just stick to IEC units).

9/4/2013 I had an error on this page. I misspelled deka, was deca. not sure how I got that. the standard has always been deka for many years and hasn't changed. see the NIST SI Prefixes Reference if you don't believe me. they set the standards, at least here in the USA. I also had the case wrong for Ki. these are corrected now.