NIST Guide to the SI, Appendix B.9: Factors for units listed by kind of quantity or field of science (2024)

Physical Measurement Laboratory

ACCELERATION
ANGLE
AREA AND SECOND MOMENT OF AREA
CAPACITY (see VOLUME)
DENSITY (that is, MASS DENSITY - see MASS DIVIDED BY VOLUME)
ELECTRICITY and MAGNETISM
ENERGY (includes WORK)
ENERGY DIVIDED BY AREA TIME
FLOW (see MASS DIVIDED BY TIME or VOLUME DIVIDED BY TIME)
FORCE
FORCE DIVIDED BY AREA (see PRESSURE)
FORCE DIVIDED BY LENGTH
HEAT
Available Energy
Coefficient of Heat Transfer
Density of Heat
Density of Heat Flow Rate
Fuel Consumption
Heat Capacity and Entropy
Heat Flow Rate
Specific Heat Capacity and
Specific Entropy
Thermal Conductivity
Thermal Diffusivity
Thermal Insulance
Thermal Resistance
Thermal Resistivity

LENGTH
LIGHT
MASS and MOMENT OF INERTIA
MASS DENSITY (see MASS DIVIDED BY VOLUME)
MASS DIVIDED BY AREA
MASS DIVIDED BY CAPACITY see MASS DIVIDED BY VOLUME)
MASS DIVIDED BY LENGTH
MASS DIVIDED BY TIME (includes FLOW)
MASS DIVIDED BY VOLUME (includes MASS DENSITY and MASS CONCENTRATION)
MOMENT OF FORCE or TORQUE
MOMENT OF FORCE or TORQUE,DIVIDED BY LENGTH
PERMEABILITY
POWER
PRESSURE or STRESS (FORCE DIVIDED BY AREA)
RADIOLOGY
SPEED (see VELOCITY)
STRESS (see PRESSURE)
TEMPERATURE
TEMPERATURE INTERVAL
TIME
TORQUE (see MOMENT OF FORCE)
VELOCITY (includes SPEED)
VISCOSITY, DYNAMIC
VISCOSITY, KINEMATIC
VOLUME (includes CAPACITY)
VOLUME DIVIDED BY TIME (includes FLOW)
WORK (see ENERGY)

Caution: The units listed in column1 are in general not to be used in NIST publications, with the exception of those few in italic type.
Factors in boldface are exact

To convert from	to	Multiply by
ACCELERATION
acceleration of free fall, standard (g_n)	meter per second squared (m/s²)	9.806 65	E+00
foot per second squared (ft/s²)	meter per second squared (m/s²)	3.048	E-01
gal (Gal)	meter per second squared (m/s²)	1.0	E-02
inch per second squared (in/s²)	meter per second squared (m/s²)	2.54	E-02

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To convert from	to	Multiply by
ANGLE
degree (°)	radian (rad)	1.745 329	E-02
gon (also called grade) (gon)	radian (rad)	1.570 796	E-02
gon (also called grade) (gon)	degree (°)	9.0	E-01
mil	radian (rad)	9.817 477	E-04
mil	degree (°)	5.625	E-02
minute (′)	radian (rad)	2.908 882	E-04
revolution (r)	radian (rad)	6.283 185	E+00
second (″)	radian (rad)	4.848 137	E-06

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To convert from	to	Multiply by
AREA AND SECOND MOMENT OF AREA
acre (based on U.S. survey foot)	square meter (m²)	4.046 873	E+03
are (a)	square meter (m²)	1.0	E+02
barn (b)	square meter (m²)	1.0	E-28
circular mil	square meter (m²)	5.067 075	E-10
circular mil	square millimeter (mm²)	5.067 075	E-04
foot to the fourth power (ft⁴)16	meter to the fourth power (m⁴)	8.630 975	E-03
hectare (ha)	square meter (m²)	1.0	E+04
inch to the fourth power (in⁴) 16	meter to the fourth power (m⁴)	4.162 314	E-07
square foot (ft²)	square meter (m²)	9.290 304	E-02
square inch (in²)	square meter (m²)	6.4516	E-04
square inch (in²)	square centimeter (cm²)	6.4516	E+00
square mile (mi²)	square meter (m²)	2.589 988	E+06
square mile (mi²)	square kilometer (km²)	2.589 988	E+00
square mile (based on U.S. survey foot) (mi²) 7	square meter (m²)	2.589 998	E+06
square mile (based on U.S. survey foot) (mi²) 7	square kilometer (km²)	2.589 998	E+00
square yard (yd²)	square meter (m²)	8.361 274	E-01

CAPACITY (see VOLUME)

DENSITY (that is, MASS DENSITY - see MASS DIVIDED BY VOLUME)

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To convert from	to	Multiply by
ELECTRICITY and MAGNETISM
abampere	ampere (A)	1.0	E+01
abcoulomb	coulomb(C)	1.0	E+01
abfarad	farad (F)	1.0	E+09
abhenry	henry (H)	1.0	E-09
abmho	siemens (S)	1.0	E+09
abohm	ohm (Ω)	1.0	E-09
abvolt	volt	1.0	E-08
ampere hour (A · h)	coulomb(C)	3.6	E+03
biot (Bi)	ampere (A)	1.0	E+01
EMU of capacitance (abfarad)	farad (F)	1.0	E+09
EMU of current (abampere)	ampere (A)	1.0	E+01
EMU of electric potential (abvolt)	volt (V)	1.0	E-08
EMU of inductance (abhenry)	henry (H)	1.0	E-09
EMU of resistance (abohm)	ohm (Ω)	1.0	E-09
ESU of capacitance (statfarad)	farad (F)	1.112 650	E-12
ESU of current (statampere)	ampere (A)	3.335 641	E-10
ESU of electric potential (statvolt)	volt (V)	2.997 925	E+02
ESU of inductance (stathenry)	henry (H)	8.987 552	E+11
ESU of resistance (statohm)	ohm (Ω)	8.987 552	E+11
faraday (based on carbon 12)	coulomb(C)	9.648 531	E+04
franklin (Fr)	coulomb(C)	3.335 641	E-10
gamma (γ)	tesla (T)	1.0	E-09
gauss (Gs, G)	tesla (T)	1.0	E-04
gilbert (Gi)	ampere (A)	7.957 747	E-01
maxwell (Mx)	weber (Wb)	1.0	E-08
mho	siemens (S)	1.0	E+00
oersted (Oe)	ampere per meter (A/m)	7.957 747	E+01
ohm centimeter (Ω · cm)	ohm meter (Ω · m)	1.0	E-02
ohm circular-mil per foot	ohm meter (Ω · m)	1.662 426	E-09
ohm circular-mil per foot	ohm square millimeter per meter (Ω · mm²/m)	1.662 426	E-03
statampere	ampere (A)	3.335 641	E-10
statcoulomb	coulomb (C)	3.335 641	E-10
statfarad	farad (F)	1.112 650	E-12
stathenry	henry (H)	8.987 552	E+11
statmho	siemens (S)	1.112 650	E-12
statohm	ohm(Ω)	8.987 552	E+11
statvolt	volt (V)	2.997 925	E+02
unit pole	weber (Wb)	1.256 637	E-07

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To convert from	to	Multiply by
ENERGY (includes WORK)
British thermal unit_IT (Btu_IT) 9	joule (J)	1.055056	E+03
British thermal unit_th (Btu_th) 9	joule (J)	1.054350	E+03
British thermal unit (mean) (Btu)	joule (J)	1.05587	E+03
British thermal unit (39 °F) (Btu)	joule (J)	1.05967	E+03
British thermal unit (59 °F) (Btu)	joule (J)	1.05480	E+03
British thermal unit (60 °F) (Btu)	joule (J)	1.05468	E+03
calorie_IT (cal_IT) 10	joule (J)	4.1868	E+00
calorie_th (cal_th) 10	joule (J)	4.184	E+00
calorie (mean) (cal)	joule (J)	4.190 02	E+00
calorie (15 °C) (cal₁₅)	joule (J)	4.185 80	E+00
calorie (20 °C) (cal₂₀)	joule (J)	4.181 90	E+00
calorie_IT, kilogram (nutrition) 11	joule (J)	4.1868	E+03
calorie_th, kilogram (nutrition) 11	joule (J)	4.184	E+03
calorie (mean), kilogram (nutrition) 11	joule (J)	4.190 02	E+03
electronvolt (eV)	joule (J)	1.602 177	E-19
erg (erg)	joule (J)	1.0	E-07
foot poundal	joule (J)	4.214 011	E-02
foot pound-force (ft · lbf)	joule (J)	1.355 818	E+00
kilocalorie_IT (kcal_IT)	joule (J)	4.1868	E+03
kilocalorie_th (kcal_th)	joule (J)	4.184	E+03
kilocalorie (mean) (kcal)	joule (J)	4.190 02	E+03
kilowatt hour (kW · h)	joule (J)	3.6	E+06
kilowatt hour (kW · h)	megajoule (MJ)	3.6	E+00
quad (10¹⁵ Btu_IT) 9	joule (J)	1.055 056	E+18
therm (EC) 24	joule (J)	1.055 06	E+08
therm (U.S.) 24	joule (J)	1.054 804	E+08
ton of TNT (energy equivalent) 25	joule (J)	4.184	E+09
watt hour (W · h)	joule (J)	3.6	E+03
watt second (W · s)	joule (J)	1.0	E+00

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To convert from	to	Multiply by
ENERGY DIVIDED BY AREA TIME
erg per square centimeter second [erg/(cm² · s)]	watt per square meter (W/m²)	1.0	E-03
watt per square centimeter (W/cm²)	watt per square meter (W/m²)	1.0	E+04
watt per square inch (W/in²)	watt per square meter (W/m²)	1.550 003	E+03
FLOW (see MASS DIVIDED BY TIME or VOLUME DIVIDED BY TIME)

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To convert from	to	Multiply by
FORCE
dyne (dyn)	newton (N)	1.0	E-05
kilogram-force (kgf)	newton (N)	9.806 65	E+00
kilopond (kilogram-force) (kp)	newton (N)	9.806 65	E+00
kip (1 kip = 1000 lbf)	newton (N)	4.448 222	E+03
kip (1 kip = 1000 lbf)	kilonewton (kN)	4.448 222	E+00
ounce (avoirdupois)-force (ozf)	newton (N)	2.780 139	E-01
poundal	newton (N)	1.382 550	E-01
pound-force (lbf) 23	newton (N)	4.448 222	E+00
pound-force per pound (lbf/lb) (thrust to mass ratio)	newton per kilogram (N/kg)	9.806 65	E+00
ton-force (2000 lbf)	newton (N)	8.896 443	E+03
ton-force (2000 lbf)	kilonewton (kN)	8.896 443	E+00
FORCE DIVIDED BY AREA (see PRESSURE)

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To convert from	to	Multiply by
FORCE DIVIDED BY LENGTH
pound-force per foot (lbf/ft)	newton per meter (N/m)	1.459 390	E+01
pound-force per inch (lbf/in)	newton per meter (N/m)	1.751 268	E+02

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To convert from	to	Multiply by
HEAT -Available Energy
British thermal unit_IT per cubicfoot (Btu_IT/ft³)	joule per cubic meter (J/m³)	3.725 895	E+04
British thermal unit_th per cubicfoot (Btu_th/ft³)	joule per cubicmeter (J/m³)	3.723 403	E+04
British thermal unit_IT per pound (Btu_IT/lb)	joule per kilogram (J/kg)	2.326	E+03
British thermal unit_th per pound (Btu_th/lb)	joule per kilogram (J/kg)	2.324 444	E+03
calorie_IT per gram (cal_IT/g)	joule per kilogram (J/kg)	4.1868	E+03
calorie_th per gram (cal_th/g)	joule per kilogram (J/kg)	4.184	E+03

To convert from	to	Multiply by
Coefficient of Heat Transfer
British thermal unit_IT per hour square foot degreeFahrenheit [Btu_IT/(h · ft² · °F)]	wattper squaremeter kelvin [W/(m² · K)]	5.678263	E+00
British thermal unit_th per hour squarefoot degreeFahrenheit [Btu_th/(h · ft² · °F)]	wattper squaremeter kelvin [W/(m² · K)]	5.674466	E+00
British thermal unit_IT per second squarefoot degreeFahrenheit [Btu_IT/(s · ft² · °F)]	wattper squaremeter kelvin [W/(m² · K)]	2.044175	E+04
British thermal unit_th per second squarefoot degreeFahrenheit [Btu_th/(s · ft² · °F)]	wattper squaremeter kelvin [W/(m² · K)]	2.042808	E+04

To convert from	to	Multiply by
Density of Heat
British thermal unit_IT per squarefoot (Btu_IT/ft²)	joule per squaremeter (J/m²)	1.135 653	E+04
British thermal unit_th per squarefoot (Btu_th/ft²)	joule per squaremeter (J/m²)	1.134 893	E+04
calorie_th per squarecentimeter (cal_th/cm²)	joule per squaremeter (J/m²)	4.184	E+04
langley (cal_th/cm²)	joule per squaremeter (J/m²)	4.184	E+04

To convert from	to	Multiply by
Density of Heat Flow Rate
British thermal unit_IT per squarefoot hour [Btu_IT/(ft² · h)]	watt per square meter (W/m²)	3.154 591	E+00
British thermal unit_th per squarefoot hour [Btu_th/(ft² · h)]	watt per square meter (W/m²)	3.152 481	E+00
British thermal unit_th per squarefoot minute [Btu_th/(ft² · min)]	watt per square meter (W/m²)	1.891 489	E+02
British thermal unit_IT per square foot second [Btu_IT/(ft² · s)]	watt per square meter (W/m²)	1.135 653	E+04
British thermal unit_th per square foot second [Btu_th/(ft² · s)]	watt per square meter (W/m²)	1.134 893	E+04
British thermal unit_th per square inch second [Btu_th/(in 2 · s)]	watt per square meter (W/m²)	1.634 246	E+06
calorie_th per square centimeter minute [cal_th/(cm² · min)]	watt per square meter (W/m²)	6.973 333	E+02
calorie_th per square centimeter second [cal_th/(cm² · s)]	watt per square meter (W/m²))	4.184	E+04

To convert from	to	Multiply by
Fuel Consumption
gallon (U.S.) per horsepower hour [gal/(hp · h)]	cubic meter per joule (m³/J)	1.410 089	E-09
gallon (U.S.) per horsepower hour [gal/(hp · h)]	liter per joule (L/J)	1.410 089	E-06
mile per gallon (U.S.) (mpg) (mi/gal)	meter per cubic meter (m/m³)	4.251 437	E+05
mile per gallon (U.S.) (mpg) (mi/gal)	kilometer per liter (km/L)	4.251 437	E-01
mile per gallon (U.S.) (mpg) (mi/gal)21	liter per 100kilometer (L/100km)	divide 235.215 by number of miles per gallon
pound per horsepower hour [lb/(hp · h)]	kilogram per joule (kg/J)	1.689 659	E-07

To convert from	to	Multiply by
Heat Capacity and Entropy
British thermal unit_IT per degree Fahrenheit (Btu_IT/°F)	joule per kelvin (J/K)	1.899 101	E+03
British thermal unit_th per degree Fahrenheit (Btu_th/°F)	joule per kelvin (J/K)	1.897 830	E+03
British thermal unit_IT per degree Rankine (Btu_IT/°R)	joule per kelvin (J/K)	1.899 101	E+03
British thermal unit_th per degree Rankine (Btu_th/°R)	joule per kelvin (J/K)	1.897 830	E+03

To convert from	to	Multiply by
Heat Flow Rate
British thermal unit_IT per hour (Btu_IT/h)	watt (W)	2.930 711	E-01
British thermal unit_th per hour (Btu_th/h)	watt (W)	2.928 751	E-01
British thermal unit_th per minute (Btu_th/min)	watt (W)	1.757 250	E+01
British thermal unit_IT per second (Btu_IT/s)	watt (W)	1.055 056	E+03
British thermal unit_th per second (Btu_th/s)	watt (W)	1.054 350	E+03
calorie_th per minute (cal_th/min)	watt (W)	6.973 333	E-02
calorie_th per second (cal_th/s)	watt (W)	4.184	E+00
kilocalorie_th per minute (kcal_th/min)	watt (W)	6.973 333	E+01
kilocalorie_th per second (kcal_th/s)	watt (W)	4.184	E+03
ton of refrigeration (12 000 Btu_IT/h)	watt (W)	3.516 853	E+03

To convert from	to	Multiply by
Specific Heat Capacity and Specific Entropy
British thermal unit_IT per pound degree Fahrenheit [Btu_IT/(lb · °F)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
British thermal unit_th per pound degree Fahrenheit [Btu_th/(lb · °F)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03
British thermal unit_IT per pound degree Rankine [Btu_IT/(lb · °R)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
British thermal unit_th per pound degree Rankine [Btu_th/(lb · °R)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03
calorie_IT per gram degree Celsius [cal_IT/(g · °C)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
calorie_th per gram degree Celsius [cal_th/(g · °C)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03
calorie_IT per gram kelvin [cal_IT/(g · K)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
calorie_th per gram kelvin [cal_th/(g · K)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03

To convert from	to	Multiply by
Thermal Conductivity
Britsh thermal unit_IT foot perhour squarefoot degreeFahrenheit [Btu_IT · ft/(h · ft² · °F)]	watt per meter kelvin [W/(m · K)]	1.730735	E+00
Britsh thermal unit_th foot perhour squarefoot degreeFahrenheit [Btu_th · ft/(h · ft² · °F)]	watt per meter kelvin [W/(m · K)]	1.729577	E+00
Britsh thermal unit_IT inch perhour squarefoot degreeFahrenheit [Btu_IT · in/(h · ft² · °F)]	watt per meter kelvin [W/(m · K)]	1.442279	E-01
Britsh thermal unit_th inch perhour squarefoot degreeFahrenheit [Btu_th · in/(h · ft² · °F)]	watt per meter kelvin [W/(m · K)]	1.441314	E-01
Britsh thermal unit_IT inch per second squarefoot degreeFahrenheit [Btu_IT · in/(s · ft² · °F)]	watt per meter kelvin [W/(m · K)]	5.192204	E+02
Britsh thermal unit_th inch per second squarefoot degreeFahrenheit [Btu_th · in/(s · ft² · °F)]	watt per meter kelvin [W/(m · K)]	5.188732	E+02
calorie_th per centimeter second degreeCelsius [cal_th/(cm · s · °C)]	watt per meter kelvin [W/(m · K)]	4.184	E+02

To convert from	to	Multiply by
Thermal Diffusivity
square foot per hour (ft²/h)	square meter per second (m²/s)	2.58064	E-05

To convert from	to	Multiply by
Thermal Insulance
clo	square meter kelvin per watt (m² · K/W)	1.55	E-01
degree Fahrenheit hour square foot per Britishthermalunit_IT(°F · h · ft²/Btu_IT)	square meter kelvin per watt (m² · K/W)	1.761 102	E-01
degree Fahrenheit hour square foot per Britishthermalunit_th(°F · h · ft²/Btu_th)	square meter kelvin per watt (m² · K/W)	1.762 280	E-01

To convert from	to	Multiply by
Thermal Resistance
degree Fahrenheit hour per British thermal unit_IT(°F · h/Btu_IT)	kelvin per watt (K/W)	1.895 634	E+00
degree Fahrenheit hour per British thermal unit_th(°F · h/Btu_th)	kelvin per watt (K/W)	1.896 903	E+00
degree Fahrenheit second per British thermal unit_IT(°F · s/Btu_IT)	kelvin per watt (K/W)	5.265 651	E-04
degree Fahrenheit second per British thermal unit_th(°F · s/Btu_th)	kelvin per watt (K/W)	5.269 175	E-04

To convert from	to	Multiply by
Thermal Resistivity
degree Fahrenheit hour square foot per Britishthermalunit_IT inch [°F · h · ft²/(Btu_IT · in)]	meter kelvin per watt (m · K/W)	6.933472	E+00
degree Fahrenheit hour square foot per Britishthermalunit_th inch [°F · h · ft²/(Btu_th · in)]	meter kelvin per watt (m · K/W)	6.938112	E+04

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To convert from	to	Multiply by
LENGTH
ångström(Å)	meter (m)	1.0	E-10
ångström(Å)	nanometer (nm)	1.0	E-01
astronomical unit (ua)	meter (m)	1.495 979	E+11
chain (based on U.S. survey foot) (ch) 7	meter (m)	2.011 684	E+01
fathom (based on U.S. survey foot) 7	meter (m)	1.828 804	E+00
fermi	meter (m)	1.0	E-15
fermi	femtometer (fm)	1.0	E+00
foot (ft)	meter (m)	3.048	E-01
foot (U.S. survey) (ft) 7	meter (m)	3.048 006	E-01
inch (in)	meter (m)	2.54	E-02
inch (in)	centimeter (cm)	2.54	E+00
kayser(K)	reciprocal meter (m^-1)	1	E+02
light year (l. y.) 18	meter (m)	9.460 73	E+15
microinch	meter (m)	2.54	E-08
microinch	micrometer (μm)	2.54	E-02
micron (μ)	meter (m)	1.0	E-06
micron (μ)	micrometer (μm)	1.0	E+00
mil (0.001 in)	meter (m)	2.54	E-05
mil (0.001 in)	millimeter (mm)	2.54	E-02
mile (mi)	meter (m)	1.609 344	E+03
mile (mi)	kilometer (km)	1.609 344	E+00
mile (based on U.S. survey foot) (mi) 7	meter (m)	1.609 347	E+03
mile (based on U.S. survey foot) (mi) 7	kilometer (km)	1.609 347	E+00
mile, nautical 20	meter (m)	1.852	E+03
parsec (pc)	meter (m)	3.085 678	E+16
pica (computer) (1/6 in)	meter (m)	4.233 333	E-03
pica (computer) (1/6 in)	millimeter (mm)	4.233 333	E+00
pica (printer's)	meter (m)	4.217 518	E-03
pica (printer's)	millimeter (mm)	4.217 518	E+00
point (computer) (1/72 in)	meter (m)	3.527 778	E-04
point (computer) (1/72 in)	millimeter (mm)	3.527 778	E-01
point (printer's)	meter (m)	3.514 598	E-04
point (printer's)	millimeter (mm)	3.514 598	E-01
rod (based on U.S. survey foot) (rd) 7	meter (m)	5.029 210	E+00
yard (yd)	meter (m)	9.144	E-01

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To convert from	to	Multiply by
LIGHT
candela per square inch (cd/in²)	candela per square meter (cd/m²)	1.550 003	E+03
footcandle	lux (lx)	1.076 391	E+01
footlambert	candela per square meter (cd/m²)	3.426 259	E+00
lambert 17	candela per square meter (cd/m²)	3.183 099	E+03
lumen per square foot (lm/ft²)	lux (lx)	1.076 391	E+01
phot (ph)	lux (lx)	1.0	E+04
stilb (sb)	candela per square meter (cd/m²)	1.0	E+04

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To convert from	to	Multiply by
MASS and MOMENT OF INERTIA
carat, metric	kilogram (kg)	2.0	E-04
carat, metric	gram (g)	2.0	E-01
grain (gr)	kilogram (kg)	6.479 891	E-05
grain (gr)	milligram (mg)	6.479 891	E+01
hundredweight (long, 112 lb)	kilogram (kg)	5.080 235	E+01
hundredweight (short, 100 lb)	kilogram (kg)	4.535 924	E+01
kilogram-force second squared per meter (kgf · s²/m)	kilogram (kg)	9.806 65	E+00
ounce (avoirdupois) (oz)	kilogram (kg)	2.834 952	E-02
ounce (avoirdupois) (oz)	gram (g)	2.834 952	E+01
ounce (troy or apothecary) (oz)	kilogram (kg)	3.110 348	E-02
ounce (troy or apothecary) (oz)	gram (g)	3.110 348	E+01
pennyweight (dwt)	kilogram (kg)	1.555 174	E-03
pennyweight (dwt)	gram (g)	1.555 174	E+00
pound (avoirdupois) (lb) 22	kilogram (kg)	4.535 924	E-01
pound (troy or apothecary) (lb)	kilogram (kg)	3.732 417	E-01
pound foot squared (lb · ft²)	kilogram meter squared (kg · m²)	4.214 011	E-02
pound inch squared (lb · in²)	kilogram meter squared (kg · m²)	2.926 397	E-04
slug (slug)	kilogram (kg)	1.459 390	E+01
ton, assay (AT)	kilogram (kg)	2.916 667	E-02
ton, assay (AT)	gram (g)	2.916 667	E+01
ton, long (2240 lb)	kilogram (kg)	1.016 047	E+03
ton, metric (t)	kilogram (kg)	1.0	E+03
tonne (called "metric ton" in U.S.) (t)	kilogram (kg)	1.0	E+03
ton, short (2000 lb)	kilogram (kg)	9.071 847	E+02

MASS DENSITY (see MASS DIVIDED BY VOLUME)

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To convert from	to	Multiply by
MASS DIVIDED BY AREA
ounce (avoirdupois) per square foot (oz/ft²)	kilogram per square meter (kg/m²)	3.051 517	E-01
ounce (avoirdupois) per square inch (oz/in²)	kilogram per square meter (kg/m²)	4.394 185	E+01
ounce (avoirdupois) per square yard (oz/yd²)	kilogram per square meter (kg/m²)	3.390 575	E-02
pound per square foot (lb/ft²)	kilogram per square meter (kg/m²)	4.882 428	E+00
pound per square inch (not pound force) (lb/in²)	kilogram per square meter (kg/m²)	7.030 696	E+02

MASS DIVIDED BY CAPACITY (see MASS DIVIDED BY VOLUME)

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To convert from	to	Multiply by
MASS DIVIDED BY LENGTH
denier	kilogram per meter (kg/m)	1.111 111	E-07
denier	gram per meter (g/m)	1.111 111	E-04
pound per foot (lb/ft)	kilogram per meter (kg/m)	1.488 164	E+00
pound per inch (lb/in)	kilogram per meter (kg/m)	1.785 797	E+01
pound per yard(lb/yd)	kilogram per meter (kg/m)	4.960 546	E-01
tex	kilogram per meter (kg/m)	1.0	E-06

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To convert from	to	Multiply by
MASS DIVIDED BY TIME (includes FLOW)
pound per hour (lb/h)	kilogram per second (kg/s)	1.259 979	E-04
pound per minute (lb/min)	kilogram per second (kg/s)	7.559 873	E-03
pound per second (lb/s)	kilogram per second (kg/s)	4.535 924	E-01
ton, short, per hour	kilogram per second (kg/s)	2.519 958	E-01

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To convert from	to	Multiply by
MASS DIVIDED BY VOLUME (includes MASS DENSITY and MASS CONCENTRATION)
grain per gallon (U.S.) (gr/gal)	kilogram per cubic meter (kg/m³)	1.711 806	E-02
grain per gallon (U.S.) (gr/gal)	milligram per liter (mg/L)	1.711 806	E+01
gram per cubic centimeter (g/cm³)	kilogram per cubic meter (kg/m³)	1.0	E+03
ounce (avoirdupois) per cubic inch (oz/in³)	kilogram per cubic meter (kg/m³)	1.729 994	E+03
ounce (avoirdupois) per gallon [Canadian and U.K. (Imperial)] (oz/gal)	kilogram per cubic meter (kg/m³)	6.236 023	E+00
ounce (avoirdupois) per gallon [Canadian and U.K. (Imperial)] (oz/gal)	gram per liter (g/L)	6.236 023	E+00
ounce (avoirdupois) per gallon (U.S.) (oz/gal)	kilogram per cubic meter (kg/m³)	7.489 152	E+00
ounce (avoirdupois) per gallon (U.S.) (oz/gal)	gram per liter (g/L)	7.489 152	E+00
pound per cubic foot (lb/ft³)	kilogram per cubic meter (kg/m³)	1.601 846	E+01
pound per cubic inch (lb/in³)	kilogram per cubic meter (kg/m³)	2.767 990	E+04
pound per cubic yard (lb/yd³)	kilogram per cubic meter (kg/m³)	5.932 764	E-01
pound per gallon [Canadian and U.K. (Imperial)] (lb/gal)	kilogram per cubic meter (kg/m³)	9.977 637	E+01
pound per gallon [Canadian and U.K. (Imperial)] (lb/gal)	kilogram per liter (kg/L)	9.977 637	E-02
pound per gallon (U.S.) (lb/gal)	kilogram per cubic meter (kg/m³)	1.198 264	E+02
pound per gallon (U.S.) (lb/gal)	kilogram per liter (kg/L)	1.198 264	E-01
slug per cubic foot (slug/ft³)	kilogram per cubic meter (kg/m³)	5.153 788	E+02
ton, long, per cubic yard	kilogram per cubic meter (kg/m³)	1.328 939	E+03
ton, short, per cubic yard	kilogram per cubic meter (kg/m³)	1.186 553	E+03

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To convert from	to	Multiply by
MOMENT OF FORCE or TORQUE
dyne centimeter (dyn · cm)	newton meter (N · m)	1.0	E-07
kilogram-force meter (kgf · m)	newton meter (N · m)	9.806 65	E+00
ounce (avoirdupois)-force inch (ozf · in)	newton meter (N · m)	7.061 552	E-03
ounce (avoirdupois)-force inch (ozf · in)	millinewton meter (mN · m)	7.061 552	E+00
pound-force foot (lbf · ft)	newton meter (N · m)	1.355 818	E+00
pound-force inch (lbf · in)	newton meter (N · m)	1.129 848	E-01

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To convert from	to	Multiply by
MOMENT OF FORCE or TORQUE, DIVIDED BY LENGTH
pound-force foot per inch (lbf · ft/in)	newton meter per meter (N · m/m)	5.337 866	E+01
pound-force inch per inch (lbf · in/in)	newton meter per meter (N · m/m)	4.448 222	E+00

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To convert from	to	Multiply by
PERMEABILITY
darcy 14	meter squared (m²)	9.869 233	E-13
perm (0 °C)	kilogram per pascal second square meter [kg/(Pa · s · m²)]	5.721 35	E-11
perm (23 °C)	kilogram per pascal second square meter [kg/(Pa · s · m²)]	5.745 25	E-11
perm inch (0 °C)	kilogram per pascal second meter [kg/(Pa · s · m)]	1.453 22	E-12
perm inch (23 °C)	kilogram per pascal second meter [kg/(Pa · s · m)]	1.459 29	E-12

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To convert from	to	Multiply by
POWER
erg per second (erg/s)	watt (W)	1.0	E-07
foot pound-force per hour (ft · lbf/h)	watt (W)	3.766 161	E-04
foot pound-force per minute (ft · lbf/min)	watt (W)	2.259 697	E-02
foot pound-force per second (ft · lbf/s)	watt (W)	1.355 818	E+00
horsepower (550 ft · lbf/s)	watt (W)	7.456 999	E+02
horsepower (boiler)	watt (W)	9.809 50	E+03
horsepower (electric)	watt (W)	7.46	E+02
horsepower (metric)	watt (W)	7.354 988	E+02
horsepower (U.K.)	watt (W)	7.4570	E+02
horsepower (water)	watt (W)	7.460 43	E+02

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To convert from	to	Multiply by
PRESSURE or STRESS (FORCE DIVIDED BY AREA)
atmosphere, standard (atm)	pascal (Pa)	1.013 25	E+05
atmosphere, standard (atm)	kilopascal (kPa)	1.013 25	E+02
atmosphere, technical (at) 8	pascal (Pa)	9.806 65	E+04
atmosphere, technical (at) 8	kilopascal (kPa)	9.806 65	E+01
bar (bar)	pascal (Pa)	1.0	E+05
bar (bar)	kilopascal (kPa)	1.0	E+02
centimeter of mercury (0 °C) 12	pascal (Pa)	1.333 22	E+03
centimeter of mercury (0 °C) 12	kilopascal (kPa)	1.333 22	E+00
centimeter of mercury, conventional (cmHg) 12	pascal (Pa)	1.333 224	E+03
centimeter of mercury, conventional (cmHg) 12	kilopascal (kPa)	1.333 224	E+00
centimeter of water (4 °C) 12	pascal (Pa)	9.806 38	E+01
centimeter of water, conventional (cmH₂O) 12	pascal (Pa)	9.806 65	E+01
dyne per square centimeter (dyn/cm²)	pascal (Pa)	1.0	E-01
foot of mercury, conventional (ftHg) 12	pascal (Pa)	4.063 666	E+04
foot of mercury, conventional (ftHg) 12	kilopascal (kPa)	4.063 666	E+01
foot of water (39.2 °F) 12	pascal (Pa)	2.988 98	E+03
foot of water (39.2 °F) 12	kilopascal (kPa)	2.988 98	E+00
foot of water, conventional (ftH₂O) 12	pascal (Pa)	2.989 067	E+03
foot of water, conventional (ftH₂O) 12	kilopascal (kPa)	2.989 067	E+00
gram-force per square centimeter (gf/cm²)	pascal (Pa)	9.806 65	E+01
inch of mercury (32 °F) 12	pascal (Pa)	3.386 38	E+03
inch of mercury (32 °F) 12	kilopascal (kPa)	3.386 38	E+00
inch of mercury (60 °F) 12	pascal (Pa)	3.376 85	E+03
inch of mercury (60 °F) 12	kilopascal (kPa)	3.376 85	E+00
inch of mercury, conventional (inHg) 12	pascal (Pa)	3.386 389	E+03
inch of mercury, conventional (inHg) 12	kilopascal (kPa)	3.386 389	E+00
inch of water (39.2 °F) 12	pascal (Pa)	2.490 82	E+02
inch of water (60 °F) 12	pascal (Pa)	2.4884	E+02
inch of water, conventional (inH₂O) 12	pascal (Pa)	2.490 889	E+02
kilogram-force per square centimeter (kgf/cm²)	pascal (Pa)	9.806 65	E+04
kilogram-force per square centimeter (kgf/cm²)	kilopascal (kPa)	9.806 65	E+01
kilogram-force per square meter (kgf/m²)	pascal (Pa)	9.806 65	E+00
kilogram-force per square millimeter (kgf/mm²)	pascal (Pa)	9.806 65	E+06
kilogram-force per square millimeter (kgf/mm²)	megapascal (MPa)	9.806 65	E+00
kip per square inch (ksi) (kip/in²)	pascal (Pa)	6.894 757	E+06
kip per square inch (ksi) (kip/in²)	kilopascal (kPa)	6.894 757	E+03
millibar (mbar)	pascal (Pa)	1.0	E+02
millibar (mbar)	kilopascal (kPa)	1.0	E-01
millimeter of mercury, conventional (mmHg) 12	pascal (Pa)	1.333 224	E+02
millimeter of water, conventional (mmH₂O) 12	pascal (Pa)	9.806 65	E+00
poundal per square foot	pascal (Pa)	1.488 164	E+00
pound-force per square foot (lbf/ft²)	pascal (Pa)	4.788 026	E+01
pound-force per square inch (psi) (lbf/in²)	pascal (Pa)	6.894 757	E+03
pound-force per square inch (psi) (lbf/in²)	kilopascal (kPa)	6.894 757	E+00
psi (pound-force per square inch) (lbf/in²)	pascal (Pa)	6.894 757	E+03
psi (pound-force per square inch) (lbf/in²)	kilopascal (kPa)	6.894 757	E+00
torr (Torr)	pascal (Pa)	1.333 224	E+02

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To convert from	to	Multiply by
RADIOLOGY
curie (Ci)	becquerel (Bq)	3.7	E+10
rad (absorbed dose) (rad)	gray (Gy)	1.0	E-02
rem (rem)	sievert (Sv)	1.0	E-02
roentgen (R)	coulomb per kilogram (C/kg)	2.58	E-04

SPEED (see VELOCITY)

STRESS (see PRESSURE)

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To convert from	to	Multiply by
TEMPERATURE
degree Celsius (°C)	kelvin (K)	T/K = t/°C + 273.15
degree centigrade 15	degree Celsius (°C)	t/°C ≈ t/deg. cent.
degree Fahrenheit (°F)	degree Celsius (°C)	t/°C = (t/°F - 32)/1.8
degree Fahrenheit (°F)	kelvin (K)	T/K = (t/°F + 459.67)/1.8
degree Rankine (°R)	kelvin (K)	T/K = (T/°R)/1.8
kelvin (K)	degree Celsius (°C)	t/°C = T/K - 273.15

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To convert from	to	Multiply by
TEMPERATURE INTERVAL
degree Celsius (°C)	kelvin (K)	1.0	E+00
degree centigrade 15	degree Celsius (°C)	1.0	E+00
degree Fahrenheit (°F)	degree Celsius (°C)	5.555 556	E-01
degree Fahrenheit (°F)	kelvin (K)	5.555 556	E-01
degree Rankine (°R)	kelvin (K)	5.555 556	E-01

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To convert from	to	Multiply by
TIME
day (d)	second (s)	8.64	E+04
day (sidereal)	second (s)	8.616 409	E+04
hour (h)	second (s)	3.6	E+03
hour (sidereal)	second (s)	3.590 170	E+03
minute (min)	second (s)	6.0	E+01
minute (sidereal)	second (s)	5.983 617	E+01
second (sidereal)	second (s)	9.972 696	E-01
shake	second (s)	1.0	E-08
shake	nanosecond (ns)	1.0	E+01
year (365 days)	second (s)	3.1536	E+07
year (sidereal)	second (s)	3.155 815	E+07
year (tropical)	second (s)	3.155 693	E+07

TORQUE (see MOMENT OF FORCE)

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To convert from	to	Multiply by
VELOCITY (includes SPEED)
foot per hour (ft/h)	meter per second (m/s)	8.466 667	E-05
foot per minute (ft/min)	meter per second (m/s)	5.08	E-03
foot per second (ft/s)	meter per second (m/s)	3.048	E-01
inch per second (in/s)	meter per second (m/s)	2.54	E-02
kilometer per hour (km/h)	meter per second (m/s)	2.777 778	E-01
knot (nautical mile per hour)	meter per second (m/s)	5.144 444	E-01
mile per hour (mi/h)	meter per second (m/s)	4.4704	E-01
mile per hour (mi/h)	kilometer per hour (km/h)	1.609 344	E+00
mile per minute (mi/min)	meter per second (m/s)	2.682 24	E+01
mile per second (mi/s)	meter per second (m/s)	1.609 344	E+03
revolution per minute (rpm) (r/min)	radian per second (rad/s)	1.047 198	E-01
rpm (revolution per minute) (r/min)	radian per second (rad/s)	1.047 198	E-01

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To convert from	to	Multiply by
VISCOSITY, DYNAMIC
centipoise (cP)	pascal second (Pa · s)	1.0	E-03
poise (P)	pascal second (Pa · s)	1.0	E-01
poundal second per square foot	pascal second (Pa · s)	1.488 164	E+00
pound-force second per square foot (lbf · s/ft²)	pascal second (Pa · s)	4.788 026	E+01
pound-force second per square inch (lbf · s/in²)	pascal second (Pa · s)	6.894 757	E+03
pound per foot hour [lb/(ft · h)]	pascal second (Pa · s)	4.133 789	E-04
pound per foot second [lb/(ft · s)]	pascal second (Pa · s)	1.488 164	E+00
rhe	reciprocal pascal second [(Pa · s)^-1]	1.0	E+01
slug per foot second [slug/(ft · s)]	pascal second (Pa · s)	4.788 026	E+01

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To convert from	to	Multiply by
VISCOSITY, KINEMATIC
centistokes (cSt)	meter squared per second (m²/s)	1.0	E-06
square foot per second (ft²/s)	meter squared per second (m²/s)	9.290 304	E-02
stokes (St)	meter squared per second (m²/s)	1.0	E-04

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To convert from	to	Multiply by
VOLUME (includes CAPACITY)
acre-foot (based on U.S. survey foot) 7	cubic meter (m³)	1.233 489	E+03
barrel [for petroleum, 42 gallons (U.S.)](bbl)	cubic meter (m³)	1.589 873	E-01
barrel [for petroleum, 42 gallons (U.S.)](bbl)	liter (L)	1.589 873	E+02
bushel (U.S.) (bu)	cubic meter (m³)	3.523 907	E-02
bushel (U.S.) (bu)	liter (L)	3.523 907	E+01
cord (128 ft³)	cubic meter (m³)	3.624 556	E+00
cubic foot (ft³)	cubic meter (m³)	2.831 685	E-02
cubic inch (in³) 13	cubic meter (m³)	1.638 706	E-05
cubic mile (mi³)	cubic meter (m³)	4.168 182	E+09
cubic yard (yd³)	cubic meter (m³)	7.645 549	E-01
cup (U.S.)	cubic meter (m³)	2.365 882	E-04
cup (U.S.)	liter (L)	2.365 882	E-01
cup (U.S.)	milliliter (mL)	2.365 882	E+02
fluid ounce (U.S.) (fl oz)	cubic meter (m³)	2.957 353	E-05
fluid ounce (U.S.) (fl oz)	milliliter (mL)	2.957 353	E+01
gallon [Canadian and U.K. (Imperial)] (gal)	cubic meter (m³)	4.546 09	E-03
gallon [Canadian and U.K. (Imperial)] (gal)	liter (L)	4.546 09	E+00
gallon (U.S.) (gal)	cubic meter (m³)	3.785 412	E-03
gallon (U.S.) (gal)	liter (L)	3.785 412	E+00
gill [Canadian and U.K. (Imperial)] (gi)	cubic meter (m³)	1.420 653	E-04
gill [Canadian and U.K. (Imperial)] (gi)	liter (L)	1.420 653	E-01
gill (U.S.) (gi)	cubic meter (m³)	1.182 941	E-04
gill (U.S.) (gi)	liter (L)	1.182 941	E-01
liter (L) 19	cubic meter (m³)	1.0	E-03
ounce [Canadian and U.K. fluid (Imperial)] (fl oz)	cubic meter (m³)	2.841 306	E-05
ounce [Canadian and U.K. fluid (Imperial)] (fl oz)	milliliter (mL)	2.841 306	E+01
ounce (U.S. fluid) (fl oz)	cubic meter (m³)	2.957 353	E-05
ounce (U.S. fluid) (fl oz)	milliliter (mL)	2.957 353	E+01
peck (U.S.) (pk)	cubic meter (m³)	8.809 768	E-03
peck (U.S.) (pk)	liter (L)	8.809 768	E+00
pint (U.S. dry) (dry pt)	cubic meter (m³)	5.506 105	E-04
pint (U.S. dry) (dry pt)	liter (L)	5.506 105	E-01
pint (U.S. liquid) (liq pt)	cubic meter (m³)	4.731 765	E-04
pint (U.S. liquid) (liq pt)	liter (L)	4.731 765	E-01
quart (U.S. dry) (dry qt)	cubic meter (m³)	1.101 221	E-03
quart (U.S. dry) (dry qt)	liter (L)	1.101 221	E+00
quart (U.S. liquid) (liq qt)	cubic meter (m³)	9.463 529	E-04
quart (U.S. liquid) (liq qt)	liter (L)	9.463 529	E-01
stere (st)	cubic meter (m³)	1.0	E+00
tablespoon	cubic meter (m³)	1.478 676	E-05
tablespoon	milliliter (mL)	1.478 676	E+01
teaspoon	cubic meter (m³)	4.928 922	E-06
teaspoon	milliliter (mL)	4.928 922	E+00
ton, register	cubic meter (m³)	2.831 685	E+00

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To convert from	to	Multiply by
VOLUME DIVIDED BY TIME (includes FLOW)
cubic foot per minute (ft³/min)	cubic meter per second (m³/s)	4.719 474	E-04
cubic foot per minute (ft³/min)	liter per second (L/s)	4.719 474	E-01
cubic foot per second (ft³/s)	cubic meter per second (m³/s)	2.831 685	E-02
cubic inch per minute (in³/min)	cubic meter per second (m³/s)	2.731 177	E-07
cubic yard per minute (yd³/min)	cubic meter per second (m³/s)	1.274 258	E-02
gallon (U.S.) per day (gal/d)	cubic meter per second (m³/s)	4.381 264	E-08
gallon (U.S.) per day (gal/d)	liter per second (L/s)	4.381 264	E-05
gallon (U.S.) per minute (gpm) (gal/min)	cubic meter per second (m³/s)	6.309 020	E-05
gallon (U.S.) per minute (gpm) (gal/min)	liter per second (L/s)	6.309 020	E-02

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WORK (see ENERGY)

Metrology

Created February 1, 2016, Updated February 17, 2022

NIST Guide to the SI, Appendix B.9: Factors for units listed by kind of quantity or field of science (2024)

Physical Measurement Laboratory

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References