Detailed list of metric system

Quantity  Unit  Symbol 

length  meter  m 
mass  kilogram  kg 
time  second  s 
electric current  ampere  A 
thermodynamic temperature  kelvin  K 
amount of substance  mole  mol 
luminous intensity  candela  cd 
Prefix  Symbol  Multiplication factor  

yotta  Y  
zetta  Z  
exa  E  
peta  P  
tera  T  
giga  G  
mega  M  1 000 000  
kilo  k  1000  
hecto  h  100  
deka  da  10  
deci  d  0.1  
centi  c  
milli  m  
micro  µ  
nano  n  
pico  p  
femto  f  
atto  a  
zepto  z  
yocto  y 
Quantity  Name  Symbol  Expression in terms of other SI units 

angle, plane  radian*  rad  m/m = 1 
angle, solid  steradian*  sr  m^{2}/m^{2} = 1 
Celsius temperature  degree Celsius  °C  K 
electric capacitance  farad  F  C/V 
electric charge, quantity of electricity  coulomb  C  A·s 
electric conductance  siemens  S  A/V 
electric inductance  henry  H  Wb/A 
electric potential difference, electromotive force  volt  V  W/A 
electric resistance  ohm  Ω  V/A 
energy, work, quantity of heat  joule  J  N·m 
force  newton  N  kg·m/s^{2} 
frequency (of a periodic phenomenon)  hertz  Hz  1/s 
illuminance  lux  lx  lm/m^{2} 
luminous flux  lumen  lm  cd·sr 
magnetic flux  weber  Wb  V·s 
magnetic flux density  tesla  T  Wb/m^{2} 
power, radiant flux  watt  W  J/s 
pressure, stress  pascal  Pa  N/m^{2} 
activity (referred to a radionuclide)  becquerel  Bq  1/s 
absorbed dose, specific energy imparted, kerma  gray  Gy  J/kg 
dose equivalent, ambient dose equivalent, directional dose equivalent, personal dose equivalent, organ dose equivalent  sievert  Sv  J/kg 
catalytic activity  katal  kat  mol/s 
* The radian and steradian, previously classified as supplementary units, are dimensionless derived units that may be used or omitted in expressing the values of physical quantities.
Quantity  Unit  Symbol  Value in SI units 

time  minute  min  1 min = 60 s 
hour  h  1 h = 60 min = 3600 s  
day  d  1 d = 24 h = 86 400 s  
week, month, etc.  
plane angle  degree*  °  1° = (pi/180) rad 
minute*  '  1' = (1/60)° = pi/10 800) rad  
second*  "  1" = (1/60)' = (pi/648 000) rad  
revolution, turn  r  1 r = 2 pi rad  
area  hectare  ha  1 ha = 1 hm^{2} = 10^{4} m^{2} 
volume  liter**  L, l  1 L = 1 dm^{3} = 10^{3} m^{3} 
mass  metric ton or tonne***  t  1 t = 10^{3} kg 
* Decimal degrees should be used for division of degrees, except for fields such as astronomy and cartography.
** The symbol L is preferred for use in the U.S.
*** The terms "metric ton" or "tonne" are restricted to commercial usage.
Name  Symbol  Value in SI Units 

nautical mile  1 nautical mile = 1852 m  
knot  1 nautical mile per hour = (1852/3600) m/s  
bar*  bar  1 bar = 100 kPa 
barn  b  1 b = 100 fm^{2} = 10^{28} m^{2} 
curie  Ci  1 Ci = 3.7 x 10^{10} Bq 
roentgen  R  1 R = 2.58 x 10^{4} C/kg 
rad  rad, rd**  1 rad = 10 mGy = 10^{2} Gy 
rem  rem  1 rem = 10 mSv = 10^{2} Sv 
* Use is limited to meteorology.
** When there is risk of confusion with the symbol for radian, rd may be used as the symbol for rad.
The above information has been compiled from various International System of Units (SI) reference publications.
For addition help see a selection of Metric posters, diagrams, and charts.
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