Many scientists have been recognized with the assignment of their names as international units by the International Committee for Weights and Measures or as non-SI units. The International System of Units (abbreviated SI from French: Système international d'unités) is the most widely used system of units of measurement. There are 7 base units and 22 derived units^[1] (excluding compound units). These units are used both in science and in commerce. Two of the base SI units and 17 of the derived units are named after scientists.^[2] 28 non-SI units are named after scientists. By this convention, their names are immortalised. As a rule, the SI units are written in lowercase letters, but symbols of units derived from the name of a person begin with a capital letter.

Scientists and SI units

(colour legend)

Name[3][4]	Life	Nationality	Quantity[5]	SI unit	Image
André-Marie Ampère[6]	1775–1836	French	Electric current[7]	ampere (A) (Base unit)
William Thomson, 1st Baron Kelvin[8]	1824–1907	British (Irish-Scottish)	Thermodynamic temperature[9]	kelvin (K) (Base unit)
Blaise Pascal[10]	1623–1662	French	Pressure[11]	pascal (Pa)
Isaac Newton[12]	1643–1727	British (English)	Force[13]	newton (N)
Anders Celsius[14]	1701–1744	Swedish	Temperature[15]	degree Celsius (°C)
Charles-Augustin de Coulomb[16]	1736–1806	French	Electric charge[17]	coulomb (C)
James Watt[18]	1736–1819	British (Scottish)	Power[19]	watt (W)
Alessandro Volta[20]	1745–1827	Italian	Electric potential[21]	volt (V)
Georg Simon Ohm[22]	1789–1855	German	Electrical resistance[23]	ohm (Ω)
Michael Faraday[24]	1791–1867	British (English)	Capacitance[25]	farad (F)
Joseph Henry[26]	1797–1878	American	Inductance[27]	henry (H)
Wilhelm Eduard Weber[28]	1804–1891	German	Magnetic flux[29]	weber (Wb)
Ernst Werner von Siemens[30]	1816–1892	German	Conductance[31]	siemens (S)
James Prescott Joule[32]	1818–1889	British (English)	Energy[33]	joule (J)
Antoine Henri Becquerel[34]	1852–1908	French	Radioactivity	becquerel (Bq)
Nikola Tesla[35]	1856–1943	Serbian[note 2]-American	Magnetic flux density[36]	tesla (T)
Heinrich Rudolf Hertz[37]	1857–1894	German	Frequency[38]	hertz (Hz)
Rolf Maximilian Sievert[39]	1896–1966	Swedish	Dose equivalent of radiation[citation needed]	sievert (Sv)
Louis Harold Gray[40]	1905–1965	British (English)	Absorbed dose of radiation[41]	gray (Gy)

Scientists and non-SI units

Name of the scientist[42][43]	Life	Nationality	Quantity	Unit[note 3]	Image
William Gilbert	1544–1603	British (English)	Magnetomotive force	gilbert (Gi)
John Napier	1550–1617	British (Scottish)	Magnitude (ln, dimensionless)	neper (Np)
Galileo Galilei	1564–1642	Italian	Acceleration	gal (Gal)
Evangelista Torricelli	1608–1647	Italian	Pressure	torr (Torr)
René Réaumur	1683–1757	French	Temperature	degree Reaumur (°R)
Daniel Gabriel Fahrenheit	1686–1736	Polish-Dutch-German	Temperature	degree Fahrenheit (°F)
Johann Heinrich Lambert	1728–1777	German	Luminance	lambert (L)
John Dalton	1766–1844	British	Mass (atomic)	dalton (Da)
Hans Christian Ørsted	1777–1851	Danish	Magnetic field	oersted (Oe)
Johann Carl Friedrich Gauss	1777–1855	German	Magnetic flux density	gauss (G)
Michael Faraday	1791–1867	British (English)	Electric charge	faraday (F)
Jean Léonard Marie Poiseuille	1797–1869	French	Dynamic viscosity	poise (P)
Anders Jonas Ångström	1814–1874	Swedish	Length	angstrom (Å)
Sir George Stokes, 1st Baronet	1818–1903	British	Kinematic viscosity	stokes (St)
William John Macquorn Rankine	1820–1872	British (Scottish)	Thermodynamic temperature	degree Rankine (°Ra )
James Clerk Maxwell	1831–1879	British (Scottish)	Magnetic flux	maxwell (Mx)
Samuel Pierpont Langley	1834–1906	American	Energy intensity	langley (Ly)
Ernst Mach	1838–1916	Austrian	Speed	Mach number (M)
John Strutt, 3rd Baron Rayleigh	1842–1919	British	Acoustic impedance	rayl
Wilhelm Röntgen	1845–1923	German	Ionizing radiation	röntgen (R)
Alexander Graham Bell	1847–1922	British (Scottish)-American	Magnitude (log10, dimensionless)	bel (B)
Loránd Eötvös	1848–1919	Hungarian	Gravitational gradient	eotvos (E)
Heinrich Kayser	1853–1940	German	Wavenumber	kayser
Joseph John Thomson	1856–1940	British	Mass-to-charge ratio	thomson (Th)
Marie Curie Pierre Curie	1867–1934 1859–1906	Polish-French	Radioactivity	curie (Ci)
Heinrich Mache	1876–1954	Austrian	Radioactivity	Mache (ME)
Peter Debye	1884–1966	Dutch	Electric dipole moment	debye (D)
Karl Guthe Jansky	1905–1950	American	Spectral irradiance	jansky (JY)
Wallace Clement Sabine	1868–1919	American	Sound absorption	sabin