Pre-defined units and сonstants
In the following, only non-prefixed units are listed. To get a more detailed information about a unit, and to get information about prefixed units, use Julia help, e.g.
help?> Unitful.kW
Unitful.kW
A prefixed unit, equal to 10^3 W.
Dimension: 𝐋² 𝐌 𝐓⁻³
See also: Unitful.W.For prefixes, see below.
Base dimensions
Amount
Mole
Unitful.molThe mole, the SI base unit for amount of substance.
Current
Ampere
Unitful.AThe ampere, the SI base unit of electric current.
Length
Angstrom
Unitful.angstrom
Unitful.ÅThe angstrom, a metric unit of length defined as 1/10 nm.
Foot
Unitful.ftThe foot, a US customary unit of length defined as 12 inch.
Inch
Unitful.inchThe inch, a US customary unit of length defined as 2.54 cm.
Meter
Unitful.mThe meter, the SI base unit of length.
Mile
Unitful.miThe mile, a US customary unit of length defined as 1760 yd.
Mil
Unitful.milThe mil, a US customary unit of length defined as 1/1000 inch.
Yard
Unitful.ydThe yard, a US customary unit of length defined as 3 ft.
Luminosity
Candela
Unitful.cdThe candela, the SI base unit of luminous intensity.
Mass
Dram
Unitful.drThe dram, a US customary unit of mass defined as 1/16 oz.
Gram
Unitful.gA prefixed unit, equal to 10^-3 kg. Note that kg, not g, is the base unit.
Grain
Unitful.grThe grain, a US customary unit of mass defined as 1/7000 lb.
Kilogram
Unitful.kgThe kilogram, the SI base unit of mass. Note that kg, not g, is the base unit.
Pound
Unitful.lbThe pound-mass, a US customary unit of mass defined as exactly 0.453,592,37 kg.
Ounce
Unitful.ozThe ounce, a US customary unit of mass defined as 1/16 lb.
Slug
Unitful.slugThe slug, a US customary unit of mass defined as 1 lbf × s^2 / ft.
UnifiedAtomicMassUnit
Unitful.uThe unified atomic mass unit, or dalton, a unit of mass defined as 1/12 the mass of an unbound neutral atom of carbon-12, equal to 1.660,539,066,60 × 10^-27 kg (the CODATA 2018 recommended value).
Temperature
Kelvin
Unitful.KThe kelvin, the SI base unit of thermodynamic temperature.
Rankine
Unitful.RaThe rankine, a US customary unit of temperature defined as 5/9 K.
Degree Celcius
Unitful.°CThe degree Celsius, an SI unit of temperature, defined such that 0 °C = 273.15 K.
Degree Fahrenheit
Unitful.°FThe degree Fahrenheit, a US customary unit of temperature, defined such that 0 °F = 459.67 Ra.
Time
Day
Unitful.dThe day, a unit of time defined as 24 hr.
Hour
Unitful.hrThe hour, a unit of time defined as 60 minutes.
Minute
Unitful.minuteThe minute, a unit of time defined as 60 s. The full name minute is used instead of the symbol min to avoid confusion with the Julia function min.
Second
Unitful.sThe second, the SI base unit of time.
Week
Unitful.wkThe week, a unit of time, defined as 7 d.
Year
Unitful.yrThe year, a unit of time, defined as 365.25 d.
Derived dimensions
Acceleration
Gal
Unitful.GalThe gal, a CGS unit of acceleration, defined as 1 cm / s^2.
EarthGravity
Unitful.geThe nominal acceleration due to gravity in a vacuum near the surface of the earth, a unit of acceleration, defined by standard to be exactly 9.806,65 m / s^2.
Unitful.gn is a quantity (with units m/s^2) whereas Unitful.ge is a unit equal to gn.
Area
Are
Unitful.aThe are, a metric unit of area, defined as 100 m^2.
Acre
Unitful.acThe acre, a US customary unit of area defined as 4840 yd^2.
Barn
Unitful.bThe barn, a metric unit of area, defined as 100 fm^2.
Hectare
Unitful.haThe hectare, a metric unit of area, defined as 100 a.
BField
Gauss
Unitful.GaussThe gauss, a CGS unit of magnetic B-field strength, defined as 1 Mx / cm^2.
Tesla
Unitful.TThe tesla, an SI unit of magnetic B-field strength, defined as 1 kg / (A × s^2).
Capacitance
Farad
Unitful.FThe farad, an SI unit of electrical capacitance, defined as 1 s^4 × A^2 / (kg × m^2).
Charge
Coulomb
Unitful.CThe coulomb, an SI unit of electric charge, defined as 1 A × s.
DynamicViscosity
Poise
Unitful.PThe poise, a CGS unit of dynamic viscosity, defined as 1 dyn × s / cm^2.
ElectricalConductance
Siemens
Unitful.SThe siemens, an SI unit of electrical conductance, defined as 1 Ω^-1.
ElectricalResistance
Ohm
Unitful.ΩThe ohm, an SI unit of electrical resistance, defined as 1 V / A.
Energy
BritishThermalUnit
Unitful.btuThe British thermal unit, a US customary unit of heat defined by ISO 31-4 as exactly 1055.06 J.
Calorie
Unitful.calThe calorie, a unit of energy defined as exactly 4.184 J.
Erg
Unitful.ergThe erg, a CGS unit of energy, defined as 1 dyn × cm.
eV
Unitful.eVThe electron-volt, a unit of energy, defined as q*V.
Joule
Unitful.JThe joule, an SI unit of energy, defined as 1 N × m.
Force
Dyne
Unitful.dynThe dyne, a CGS unit of force, defined as 1 g × cm / s^2.
PoundsForce
Unitful.lbfThe pound-force, a US customary unit of force defined as 1 lb × ge.
Newton
Unitful.NThe newton, an SI unit of force, defined as 1 kg × m / s^2.
Frequency
Becquerel
Unitful.BqThe becquerel, an SI unit of radioactivity, defined as 1 nuclear decay per s.
Hertz
Unitful.HzThe hertz, an SI unit of frequency, defined as 1 s^-1.
AngHertz
Unitful.Hz2πA unit for convenience in angular frequency, equal to 2π Hz.
RevolutionsPerMinute
Unitful.rpmRevolutions per minute, a unit of rotational speed, defined as 2π rad / minute.
RevolutionsPerSecond
Unitful.rpsRevolutions per second, a unit of rotational speed, defined as 2π rad / s.
HField
Oersted
Unitful.OeThe oersted, a CGS unit of magnetic H-field strength, defined as 1000 A / (4π × m).
Inductance
Henry
Unitful.HThe henry, an SI unit of electrical inductance, defined as 1 J / A^2.
KinematicViscosity
Stokes
Unitful.StThe stokes, a CGS unit of kinematic viscosity, defined as 1 cm^2 / s.
Luminous flux
Lumen
Unitful.lmThe lumen, an SI unit of luminous flux, defined as 1 cd × sr.
MagneticFlux
Maxwell
Unitful.MxThe maxwell, a CGS unit of magnetic flux, defined as 1 Gauss × cm^2.
Weber
Unitful.WbThe weber, an SI unit of magnetic flux, defined as 1 kg × m^2 / (A × s^2).
MolarFlow
Katal
Unitful.katThe katal, an SI unit of catalytic activity, defined as 1 mol of catalyzed substrate per s.
Molarity
Molar
Unitful.MA unit for measuring molar concentration, equal to 1 mol/L.
Power
Watt
Unitful.WThe watt, an SI unit of power, defined as 1 J / s.
Pressure
Atmosphere
Unitful.atmThe standard atmosphere, a unit of pressure, defined as 101,325 Pa.
Barye
Unitful.BaThe barye, a CGS unit of pressure, defined as 1 dyn / cm^2.
Bar
Unitful.barThe bar, a metric unit of pressure, defined as 100 kPa.
Pascal
Unitful.PaThe pascal, an SI unit of pressure, defined as 1 N / m^2.
PoundsPerSquareInch
Unitful.psiPounds per square inch, a US customary unit of pressure defined as 1 lbf / inch^2.
Torr
Unitful.TorrThe torr, a unit of pressure, defined as 1/760 atm.
Velocity
SpeedOfLight
Unitful.cThe speed of light in a vacuum, a unit of speed, defined as exactly 2.997,924,58 × 10^8 m/s.
Unitful.c0 is a quantity (with units m/s) whereas Unitful.c is a unit equal to c0.
Voltage
Volt
Unitful.VThe volt, an SI unit of electric potential, defined as 1 W / A.
Volume
Liter
Unitful.L
Unitful.lThe liter, a metric unit of volume, defined as 1000 cm^3.
Dimensionless units
Percentmille
Unitful.pcmPercentmille, a unit meaning parts per hundred thousand.
Percent
Unitful.percentPercent, a unit meaning parts per hundred. Printed as "%".
Permille
Unitful.permillePermille, a unit meaning parts per thousand. Printed as "‰".
Pertenthousand
Unitful.pertenthousandPermyriad, a unit meaning parts per ten thousand. Printed as "‱".
Perbillion
Unitful.ppbPerbillion, a unit meaning parts per billion (in the short-scale sense), i.e., 10^-9.
Permillion
Unitful.ppmPermillion, a unit meaning parts per million.
Perquadrillion
Unitful.ppqPerquadrillion, a unit meaning parts per quadrillion (in the short-scale sense), i.e., 10^-15.
Pertrillion
Unitful.pptPertrillion, a unit meaning parts per trillion (in the short-scale sense), i.e., 10^-12.
Radian
Unitful.radThe radian, a unit of angle. There are 2π rad in a circle.
Steradian
Unitful.srThe steradian, a unit of spherical angle. There are 4π sr in a sphere.
Degree
Unitful.°The degree, a unit of angle. There are 360° in a circle.
Logarithmic units
| Unit | Name |
|---|---|
dB | Decibel |
B | Bel |
Np | Neper |
cNp | Centineper |
Log units related to reference levels
| Unit | Reference level |
|---|---|
dBHz | 1Hz |
dBm | 1mW |
dBV | 1V |
dBu | sqrt(0.6)V |
dBμV | 1μV |
dBSPL | 20μPa |
dBFS | RootPowerRatio(1) |
dBΩ | 1Ω |
dBS | 1S |
Physical constants
G
Unitful.GA quantity representing the universal gravitational constant, equal to 6.674,30 × 10^-11 m^3 / (kg × s^2) (the CODATA 2018 recommended value).
Na
Unitful.NaA quantity representing Avogadro's constant, defined as exactly 6.022,140,76 × 10^23 / mol.
R
Unitful.RA quantity representing the molar gas constant, defined as Na × k.
R∞
Unitful.R∞A quantity representing the Rydberg constant, equal to 1.097,373,156,8160 × 10^-7 / m (the CODATA 2018 recommended value).
Z0
Unitful.Z0A quantity representing the impedance of free space, a constant defined as μ0 × c.
c0
Unitful.c0A quantity representing the speed of light in a vacuum, defined as exactly 2.997,924,58 × 10^8 m/s.
Unitful.c0 is a quantity (with units m/s) whereas Unitful.c is a unit equal to c0.
gn
Unitful.gnA quantity representing the nominal acceleration due to gravity in a vacuum near the surface of the earth, defined by standard to be exactly 9.806,65 m / s^2.
Unitful.gn is a quantity (with units m/s^2) whereas Unitful.ge is a unit equal to gn.
h
Unitful.hA quantity representing Planck's constant, defined as exactly 6.626,070,15 × 10^-34 J × s.
k
Unitful.kA quantity representing the Boltzmann constant, defined as exactly 1.380,649 × 10^-23 J / K.
me
Unitful.meA quantity representing the rest mass of an electron, equal to 9.109,383,7015 × 10^-31 kg (the CODATA 2018 recommended value).
mn
Unitful.mnA quantity representing the rest mass of a neutron, equal to 1.674,927,498,04 × 10^-27 kg (the CODATA 2018 recommended value).
mp
Unitful.mpA quantity representing the rest mass of a proton, equal to 1.672,621,923,69 × 10^-27 kg (the CODATA 2018 recommended value).
q
Unitful.qA quantity equal to the elementary charge, the charge of a single electron, with a value of exactly 1.602,176,634 × 10^-19 C. The letter q is used instead of e to avoid confusion with Euler's number.
ħ
Unitful.ħA quantity representing the reduced Planck constant, defined as h / 2π.
Φ0
Unitful.Φ0A quantity representing the superconducting magnetic flux quantum, defined as h / (2 × q).
ε0, ϵ0
Unitful.ε0
Unitful.ϵ0A quantity representing the vacuum permittivity constant, defined as 1 / (μ0 × c^2).
μ0
Unitful.μ0A quantity representing the vacuum permeability constant, defined as 4π × 10^-7 H / m.
μB
Unitful.μBA quantity representing the Bohr magneton, equal to q × ħ / (2 × me).
σ
Unitful.σA quantity representing the Stefan-Boltzmann constant, defined as π^2 × k^4 / (60 × ħ^3 × c^2).
Metric (SI) Prefixes
| Prefix | Name | Power of Ten |
|---|---|---|
| y | yocto | -24 |
| z | zepto | -21 |
| a | atto | -18 |
| f | femto | -15 |
| p | pico | -12 |
| n | nano | -9 |
| μ | micro | -6 |
| m | milli | -3 |
| c | centi | -2 |
| d | deci | -1 |
| da | deca | 1 |
| h | hecto | 2 |
| k | kilo | 3 |
| M | mega | 6 |
| G | giga | 9 |
| T | tera | 12 |
| P | peta | 15 |
| E | exa | 18 |
| Z | zetta | 21 |
| Y | yotta | 24 |