{"id":53,"date":"2006-05-31T10:52:59","date_gmt":"2006-05-31T10:52:59","guid":{"rendered":"https:\/\/www.garfnet.org.uk\/cms\/metric-si-units\/"},"modified":"2025-10-27T02:35:53","modified_gmt":"2025-10-27T02:35:53","slug":"metric-si-units","status":"publish","type":"page","link":"https:\/\/garfnet.org.uk\/cms\/tables\/general\/metric-si-units\/","title":{"rendered":"Metric units"},"content":{"rendered":"

The International System of Units is abbreviated “SI” from the French “le Syst\u00e8me international d’unit\u00e9s”. SI is the modern form of the metric system and is a coherent and definable measurement system devised around multiples of ten. It is the planet’s most widely used system of measurement, both for everyday commerce and for engineering, science and technology.<\/b><\/p>\n

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Base SI units<\/h2>\n\n\n\n\n\n\n\n\n\n\n
Quantity<\/b><\/div><\/th>\n
Unit<\/b><\/div><\/th>\n
Symbol<\/b><\/div><\/th>\n
Equivalent<\/b><\/div><\/th>\n
Equivalent<\/b><\/div><\/th>\n<\/tr>\n
Length<\/div><\/td>\n
metre<\/div><\/td>\n
m<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Mass<\/div><\/td>\n
kilogram<\/div><\/td>\n
kg<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Time<\/div><\/td>\n
second<\/div><\/td>\n
s<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Electric current<\/div><\/td>\n
ampere<\/div><\/td>\n
A<\/div><\/td>\n
C\/s<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Absolute temperature<\/div><\/td>\n
kelvin<\/div><\/td>\n
K<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Amount of substance<\/div><\/td>\n
mole<\/div><\/td>\n
mol<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Luminous intensity<\/div><\/td>\n
candela<\/div><\/td>\n
cd<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Coherent derived SI units<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Quantity<\/b><\/div><\/th>\n
Unit<\/b><\/div><\/th>\n
Symbol<\/b><\/div><\/th>\n
Equivalent<\/b><\/div><\/th>\n
Equivalent<\/b><\/div><\/th>\n<\/tr>\n
Plane angle<\/div><\/td>\n
radian<\/div><\/td>\n
rad<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Solid angle<\/div><\/td>\n
steradian<\/div><\/td>\n
sr<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Frequency<\/div><\/td>\n
hertz<\/div><\/td>\n
Hz<\/div><\/td>\n
1\/s<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Force<\/div><\/td>\n
newton<\/div><\/td>\n
N<\/div><\/td>\n
kg m\/s\u00b2<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Energy<\/div><\/td>\n
joule<\/div><\/td>\n
J<\/div><\/td>\n
Nm<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Power<\/div><\/td>\n
watt<\/div><\/td>\n
W<\/div><\/td>\n
J\/s<\/div><\/td>\n
VA<\/div><\/td>\n<\/tr>\n
Electric Charge<\/div><\/td>\n
coulomb<\/div><\/td>\n
C<\/div><\/td>\n
As<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Voltage \u2013 potential difference<\/div><\/td>\n
volt<\/div><\/td>\n
V<\/div><\/td>\n
W\/A<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Electrical capacitance<\/div><\/td>\n
farad<\/div><\/td>\n
F<\/div><\/td>\n
C\/V<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Electrical resistance<\/div><\/td>\n
ohm<\/div><\/td>\n
W<\/div><\/td>\n
V\/A<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Magnetic flux<\/div><\/td>\n
weber<\/div><\/td>\n
Wb<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Magnetic flux density<\/div><\/td>\n
tesla<\/div><\/td>\n
T<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Inductance<\/div><\/td>\n
henry<\/div><\/td>\n
H<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Luminous Flux<\/div><\/td>\n
lumen<\/div><\/td>\n
lm<\/div><\/td>\n
\u00a0<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Illumination<\/div><\/td>\n
lux<\/div><\/td>\n
lx<\/div><\/td>\n
lm\/m\u00b2<\/div><\/td>\n
\u00a0<\/div><\/td>\n<\/tr>\n
Volume<\/div><\/td>\n
litre<\/div><\/td>\n
L<\/div><\/td>\n
0.001\u00a0m3<\/sup><\/span><\/div><\/td>\n
1\u00a0dm3<\/sup><\/span><\/div><\/td>\n<\/tr>\n
Temperature<\/div><\/td>\n
Celsius<\/div><\/td>\n
\u00b0 C<\/div><\/td>\n
Kelvin-273.15 K
\n<\/span><\/div><\/td>\n
\u00a0<\/span><\/div><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
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Further reading<\/h2>\n