Units

Every unit AE accepts when you type a value, grouped by physical dimension. Each row carries the exact factor and offset that take it to SI, so a value entered in any unit means the same thing to the solver. Looking for a physical constant instead? Constants.

Unit converter

ValueUnit typeFromTo

Result1000 mA

Only units sharing the dimension I are offered as targets, so a conversion can never cross dimensions.

dimensionlessArea to sonic-throat area ratio, Density ratio across shock, Downstream Mach number, Fanno friction parameter, Pitot to upstream static pressure ratio, Stagnation pressure ratio across shock, Stagnation pressure to critical ratio, Stagnation temperature to critical ratio, Static pressure ratio across shock, Static pressure to critical ratio, Static temperature ratio across shock, Static temperature to critical ratio, Static-to-stagnation density ratio, Static-to-stagnation pressure ratio, Static-to-stagnation temperature ratio, Velocity to critical velocity ratio, Substance, Water content

Unit	Symbol	Key	× to SI	+ offset	Used for
bar cubic metre squared root-kelvin per kilomole squared	bar·(m³/kmol)²·K⁰·⁵	bar_m6_K05_per_kmol2	1	—
bar cubic metre squared per kilomole squared	bar·(m³/kmol)²	bar_m6_per_kmol2	1	—
degree	°	deg	0.0174532925	—
dimensionless	-	dimensionless	1	—	Area to sonic-throat area ratio, Density ratio across shock, Downstream Mach number, Fanno friction parameter, Pitot to upstream static pressure ratio, Stagnation pressure ratio across shock, Stagnation pressure to critical ratio, Stagnation temperature to critical ratio, Static pressure ratio across shock, Static pressure to critical ratio, Static temperature ratio across shock, Static temperature to critical ratio, Static-to-stagnation density ratio, Static-to-stagnation pressure ratio, Static-to-stagnation temperature ratio, Velocity to critical velocity ratio
no unit	-	none	1	—	Substance
percent	%	percent	0.01	—	Water content
parts per million	ppm	ppm	10⁻⁶	—
radian	rad	rad	1	—

IElectric current

Unit	Symbol	Key	× to SI	+ offset	Used for
ampere	A	A	1	—	Electric current
milliampere	mA	mA	0.001	—

KAdiabatic flame temperature, Adiabatic saturation temperature, Critical temperature, Dew-point temperature, Freezing point, Normal boiling point, Saturation temperature, Stagnation temperature, Temperature, Wet-bulb temperature

Unit	Symbol	Key	× to SI	+ offset	Used for
degree Celsius	°C	C	1	273.15
degree Fahrenheit	°F	F	0.555555556	255.372222
kelvin	K	K	1	—	Adiabatic flame temperature, Adiabatic saturation temperature, Critical temperature, Dew-point temperature, Freezing point, Normal boiling point, Saturation temperature, Stagnation temperature, Temperature, Wet-bulb temperature
degree Rankine	R	R	0.555555556	—

K⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
per kelvin	1/K	per_K	1	—

K⁻²

Unit	Symbol	Key	× to SI	+ offset	Used for
per kelvin squared	1/K²	per_K2	1	—

K⁻³

Unit	Symbol	Key	× to SI	+ offset	Used for
per kelvin cubed	1/K³	per_K3	1	—

K⁻⁴

Unit	Symbol	Key	× to SI	+ offset	Used for
per kelvin to the fourth	1/K⁴	per_K4	1	—

LElevation, Length, Liquid column height

Unit	Symbol	Key	× to SI	+ offset	Used for
centimetre	cm	cm	0.01	—
foot	ft	ft	0.3048	—
inch	in	in	0.0254	—
kilometer	km	km	1000	—
metre	m	m	1	—	Elevation, Length, Liquid column height
mile	mi	mile	1609.344	—
millimeter	mm	mm	0.001	—

L²Area

Unit	Symbol	Key	× to SI	+ offset	Used for
square centimetre	cm²	cm2	10⁻⁴	—
square foot	ft²	ft2	0.09290304	—
square inch	in²	in2	6.4516 × 10⁻⁴	—
square metre	m²	m2	1	—	Area
square millimeter	mm²	mm2	10⁻⁶	—

L²·T⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
centistokes	cSt	cSt	10⁻⁶	—
square meter per second (kinematic viscosity)	m²/s	m2_per_s	1	—

L²·T⁻²Latent heat of fusion, Latent heat of vaporization

Unit	Symbol	Key	× to SI	+ offset	Used for
Btu per pound-mass	Btu/lbm	Btu_per_lbm	2326	—
joule per kilogram	J/kg	J_per_kg	1	—	Latent heat of fusion, Latent heat of vaporization
kilojoule per kilogram	kJ/kg	kJ_per_kg	1000	—

L²·T⁻²·K⁻¹Specific heat above freezing, Specific heat below freezing

Unit	Symbol	Key	× to SI	+ offset	Used for
Btu per pound-mass Rankine	Btu/lbm·R	Btu_per_lbmR	4186.8	—
joule per kilogram kelvin	J/kg·K	J_per_kgK	1	—	Specific heat above freezing, Specific heat below freezing
kilojoule per kilogram kelvin	kJ/kg·K	kJ_per_kgK	1000	—

L²·T⁻³·K⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
kilojoule per kilogram kelvin second	kJ/kg·K·s	kJ_per_kgK_s	1000	—

L³

Unit	Symbol	Key	× to SI	+ offset
cubic foot	ft³	ft3	0.0283168466	—
US gallon	gal	gal	0.00378541178	—
litre	L	L	0.001	—
cubic metre	m³	m3	1	—
cubic millimeter	mm³	mm3	10⁻⁹	—

L³·N⁻¹Critical molar volume

Unit	Symbol	Key	× to SI	+ offset	Used for
cubic foot per pound-mole	ft³/lbmol	ft3_per_lbmol	6.24279606 × 10⁻⁵	—
cubic metre per kilomole	m³/kmol	m3_per_kmol	0.001	—	Critical molar volume

L³·T⁻¹

Unit	Symbol	Key	× to SI	+ offset
cubic foot per second	ft³/s	ft3_per_s	0.0283168466	—
US gallon per minute	gpm	gal_per_min	6.30901964 × 10⁻⁵	—
litre per second	L/s	L_per_s	0.001	—
cubic metre per second	m³/s	m3_per_s	1	—

L·T⁻¹

Unit	Symbol	Key	× to SI	+ offset
foot per second	ft/s	ft_per_s	0.3048	—
kilometre per hour	km/h	km_per_h	0.277777778	—
metre per second	m/s	m_per_s	1	—
mile per hour	mph	mph	0.44704	—

L·T⁻²

Unit	Symbol	Key	× to SI	+ offset	Used for
foot per second squared	ft/s²	ft_per_s2	0.3048	—
metre per second squared	m/s²	m_per_s2	1	—

MMass

Unit	Symbol	Key	× to SI	+ offset	Used for
gram	g	g	0.001	—
kilogram	kg	kg	1	—	Mass
pound-mass	lbm	lbm	0.45359237	—
slug	slug	slug	14.5939029	—
metric ton	t	tonne	1000	—

M·L⁻¹·T⁻¹Dynamic viscosity

Unit	Symbol	Key	× to SI	+ offset	Used for
centipoise	cP	cP	0.001	—
pascal second (dynamic viscosity)	Pa·s	Pa_s	1	—	Dynamic viscosity

M·L⁻¹·T⁻²Atmospheric pressure, Critical pressure, Gage pressure, Mean effective pressure, Partial pressure, Pressure, Saturation pressure, Stagnation pressure, Vacuum pressure

Unit	Symbol	Key	× to SI	+ offset	Used for
standard atmosphere	atm	atm	101325	—
bar	bar	bar	100000	—
inch of mercury	inHg	inHg	3386.38864	—
kilogram-force per square centimeter	kgf/cm²	kgf_per_cm2	98066.5	—
kilopascal	kPa	kPa	1000	—
pound-force per square foot	lbf/ft²	lbf_per_ft2	47.880259	—
meter of water column	mH2O	mH2O	9806.65	—
millimeter of mercury	mmHg	mmHg	133.322387	—
megapascal	MPa	MPa	10⁶	—
pascal	Pa	Pa	1	—	Atmospheric pressure, Critical pressure, Gage pressure, Mean effective pressure, Partial pressure, Pressure, Saturation pressure, Stagnation pressure, Vacuum pressure
pound per square inch	psi	psi	6894.75729	—
pound per square inch absolute	psia	psia	6894.75729	—
pound per square inch gage	psig	psig	6894.75729	—
torr	torr	torr	133.322368	—

M·L⁻²·T⁻²

Unit	Symbol	Key	× to SI	+ offset	Used for
kilonewton per cubic meter	kN/m³	kN_per_m3	1000	—
newton per cubic meter	N/m³	N_per_m3	1	—

M·L⁻³

Unit	Symbol	Key	× to SI	+ offset	Used for
kilogram per cubic metre	kg/m³	kg_per_m3	1	—
pound-mass per cubic foot	lbm/ft³	lbm_per_ft3	16.0184634	—

M·L²

Unit	Symbol	Key	× to SI	+ offset	Used for
kilogram square meter (moment of inertia)	kg·m²	kg_m2	1	—

M·L²·T⁻²Enthalpy, Exergy, Exergy destruction, Gibbs function, Heat, Helmholtz function, Internal energy, Irreversibility, Kinetic energy, Potential energy, Reversible work, Total energy, Work, Torque

Unit	Symbol	Key	× to SI	+ offset	Used for
British thermal unit	Btu	Btu	1055.05585	—
calorie	cal	cal	4.184	—
foot pound-force	ft·lbf	ft_lbf	1.35581795	—
joule	J	J	1	—	Enthalpy, Exergy, Exergy destruction, Gibbs function, Heat, Helmholtz function, Internal energy, Irreversibility, Kinetic energy, Potential energy, Reversible work, Total energy, Work
kilocalorie	kcal	kcal	4184	—
kilojoule	kJ	kJ	1000	—
kilowatt-hour	kW·h	kWh	3.6 × 10⁶	—
pound-force foot (torque)	lbf·ft	lbf_ft	1.35581795	—
megajoule	MJ	MJ	10⁶	—
newton meter (torque)	N·m	N_m	1	—	Torque
therm	therm	therm	1.05505585 × 10⁸	—

M·L²·T⁻²·I⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
weber	Wb	Wb	1	—

M·L²·T⁻²·I⁻²

Unit	Symbol	Key	× to SI	+ offset	Used for
henry	H	H_henry	1	—
millihenry	mH	mH	0.001	—

M·L²·T⁻²·K⁻¹

Unit	Symbol	Key	× to SI	+ offset
Btu per Rankine	Btu/R	Btu_per_R	1899.10053	—
joule per kelvin	J/K	J_per_K	1	—
kilojoule per kelvin	kJ/K	kJ_per_K	1000	—

M·L²·T⁻²·K⁻¹·N⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
joule per kilomole kelvin	J/(kmol·K)	J_per_kmolK	1	—
kilojoule per kilomole kelvin	kJ/kmol·K	kJ_per_kmolK	1	—

M·L²·T⁻²·N⁻¹Gibbs function of formation, Standard molar chemical exergy, Standard molar chemical exergy (Model I), Standard molar chemical exergy (Model II)

Unit	Symbol	Key	× to SI	+ offset	Used for
Btu per pound-mole	Btu/lbmol	Btu_per_lbmol	2.326	—
joule per kilomole	J/kmol	J_per_kmol	1	—	Gibbs function of formation, Standard molar chemical exergy
kilojoule per kilomole	kJ/kmol	kJ_per_kmol	1	—	Standard molar chemical exergy (Model I), Standard molar chemical exergy (Model II)

M·L²·T⁻³Exergy destruction rate, Exergy rate, Heat rate, Power

Unit	Symbol	Key	× to SI	+ offset	Used for
Btu per hour	Btu/h	Btu_per_h	0.29307107	—
Btu per second	Btu/s	Btu_per_s	1055.05585	—
horsepower	hp	hp	745.699872	—
kilojoule per second	kJ/s	kJ_per_s	1000	—
kilowatt	kW	kW	1000	—
megawatt	MW	MW	10⁶	—
ton of refrigeration	ton	ton_ref	3516.85284	—
watt	W	W	1	—	Exergy destruction rate, Exergy rate, Heat rate, Power

M·L²·T⁻³·I⁻¹Electric potential

Unit	Symbol	Key	× to SI	+ offset	Used for
millivolt	mV	mV	0.001	—
volt	V	V	1	—	Electric potential

M·L²·T⁻³·I⁻²

Unit	Symbol	Key	× to SI	+ offset	Used for
kilohm	kohm	kohm	1000	—
ohm	ohm	ohm	1	—

M·L²·T⁻³·K⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
kilowatt per kelvin	kW/K	kW_per_K	1000	—

M·L·T⁻²Buoyant force, Force, Weight

Unit	Symbol	Key	× to SI	+ offset	Used for
kilonewton	kN	kN	1000	—
pound-force	lbf	lbf	4.44822162	—
newton	N	N	1	—	Buoyant force, Force, Weight

M·L·T⁻³·K⁻¹Thermal conductivity

Unit	Symbol	Key	× to SI	+ offset	Used for
Btu per hour foot Rankine	Btu/h·ft·R	Btu_per_hftR	1.73073467	—
watt per metre kelvin	W/m·K	W_per_mK	1	—	Thermal conductivity

M·N⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
kilogram per kilomole	kg/kmol	kg_per_kmol	0.001	—
pound-mass per pound-mole	lbm/lbmol	lbm_per_lbmol	0.001	—

M·T⁻¹

Unit	Symbol	Key	× to SI	+ offset
kilogram per hour	kg/h	kg_per_h	2.77777778 × 10⁻⁴	—
kilogram per second	kg/s	kg_per_s	1	—
pound-mass per hour	lbm/h	lbm_per_h	1.25997826 × 10⁻⁴	—
pound-mass per second	lbm/s	lbm_per_s	0.45359237	—
newton second per meter (damping)	N·s/m	N_s_per_m	1	—

M·T⁻²

Unit	Symbol	Key	× to SI	+ offset	Used for
newton per meter (stiffness)	N/m	N_per_m	1	—

M·T⁻²·I⁻¹

Unit	Symbol	Key	× to SI	+ offset	Used for
tesla	T	Tesla	1	—

M·T⁻³Heat flux

Unit	Symbol	Key	× to SI	+ offset	Used for
watt per square meter	W/m²	W_per_m2	1	—	Heat flux

M·T⁻³·K⁻¹Convection heat transfer coefficient

Unit	Symbol	Key	× to SI	+ offset	Used for
Btu per hour square foot Rankine	Btu/h·ft²·R	Btu_per_hft2R	5.6782634	—
watt per square meter kelvin	W/m²·K	W_per_m2K	1	—	Convection heat transfer coefficient

M⁻¹·L⁻²·T³·I²

Unit	Symbol	Key	× to SI	+ offset	Used for
siemens	S	S	1	—

M⁻¹·L⁻²·T⁴·I²

Unit	Symbol	Key	× to SI	+ offset
farad	F	F_farad	1	—
picofarad	pF	pF	10⁻¹²	—
microfarad	uF	uF	10⁻⁶	—

M⁻¹·L³

Unit	Symbol	Key	× to SI	+ offset	Used for
cubic foot per pound-mass	ft³/lbm	ft3_per_lbm	0.0624279606	—
cubic metre per kilogram	m³/kg	m3_per_kg	1	—

NAmount of substance

Unit	Symbol	Key	× to SI	+ offset	Used for
kilomole	kmol	kmol	1000	—
pound-mole	lbmol	lbmol	453.59237	—
mole	mol	mol	1	—	Amount of substance

TTime

Unit	Symbol	Key	× to SI	+ offset	Used for
day	day	day	86400	—
hour	h	h	3600	—
minute	min	min	60	—
second	s	s	1	—	Time
year	yr	year	3.15576 × 10⁷	—

T·I

Unit	Symbol	Key	× to SI	+ offset	Used for
coulomb	C	C_coulomb	1	—

T⁻¹Angular velocity

Unit	Symbol	Key	× to SI	+ offset	Used for
hertz	Hz	Hz	1	—
radian per second	rad/s	rad_per_s	1	—	Angular velocity
revolution per minute	rpm	rpm	0.104719755	—

T⁻¹·N

Unit	Symbol	Key	× to SI	+ offset	Used for
kilomole per second	kmol/s	kmol_per_s	1000	—

The seven fundamental dimensions

Dimension	SI unit	AE code
Length	meter (m)	L
Mass	kilogram (kg)	M
Time	second (s)	T
Temperature	kelvin (K)	K
Electric current	ampere (A)	I
Amount of light	candela (cd)	J
Amount of matter	mole (mol)	N

SI unit prefixes

Factor	Prefix	Symbol
10²⁴	yotta	Y
10²¹	zetta	Z
10¹⁸	exa	E
10¹⁵	peta	P
10¹²	tera	T
10⁹	giga	G
10⁶	mega	M
10³	kilo	k
10²	hecto	h
10¹	deka	da
10⁻¹	deci	d
10⁻²	centi	c
10⁻³	milli	m
10⁻⁶	micro	μ
10⁻⁹	nano	n
10⁻¹²	pico	p
10⁻¹⁵	femto	f
10⁻¹⁸	atto	a
10⁻²¹	zepto	z
10⁻²⁴	yocto	y

Specific gravities at 0 °C

SG = ρ / ρ_H₂O, with ρ_H₂O = 1000 kg/m³. Specific weight is γ_s = ρ g.

Substance	SG
Water	1.0
Blood	1.05
Seawater	1.025
Gasoline	0.7
Ethyl alcohol	0.79
Mercury	13.6
Wood	0.3–0.9
Gold	19.2
Bones	1.7–2.0
Ice	0.92
Air (at 1 atm)	0.0013

Temperature scales

Kelvin → Rankine	T(°R) = 1.8 T(K)
Kelvin → Celsius	T(°C) = T(K) − 273.15
Rankine → Fahrenheit	T(°F) = T(°R) − 459.67
Celsius → Fahrenheit	T(°F) = 1.8 T(°C) + 32
Interval equality	ΔT(K) = ΔT(°C), ΔT(°R) = ΔT(°F)