バージョン9からUnits`パッケージに代り，Quantityを介して新しい単位フレームワークが使われるようになった．

Units`パッケージは，さまざまな科学的分野の単位に対して広く使われる単位を提供してきた．Quantityにより提供される単位フレームワークが，完全にこれに代るものとなっている．

新しいシステムでは，以前の単位すべてが基本単位として与えられ，Quantity式の中の文字列として表される．Convert，ConvertTemperature，SI等の関数は，目標単位でも目標単位系でも取ることのできるUnitConvertに統合されている．

変換関数

Units`	バージョン9
Convert[expr, newunits]	UnitConvert[quantity, newunits]
ConvertTemperature[expr, newunits]	UnitConvert[quantity, newunits]
SI[expr]	UnitConvert[quantity, "SI"]

SI接頭辞

kilo，micro，yotta等のSI接頭辞が適切なSI単位に統合され，「kilometers」や「yottaseconds」等の単位名が構成できるようになった．

数量と単位

Quantityは慣用的な単位名を使う．そのほとんどは以前の単位名の複数形であるが，未知の単位名を自動的に解釈する機能も備えている．

Units`パッケージに含まれているすべての単位に相当するものをはじめ，その他の単位も含まれている．

長さの単位

Units`	バージョン9
Angstrom	Quantity["Angstroms"]
AU	Quantity["AstronomicalUnit"]
AstronomicalUnit	Quantity["AstronomicalUnit"]
Bolt	Quantity["BoltsLength"]
Cable	Quantity["CableLengthsUSNavy"]
Caliber	Quantity["Calibres"]
Centimeter	Quantity["Centimeters"]
Chain	Quantity["GuntersChains"]
Cicero	Quantity["Ciceros"]
Cubit	Quantity["Cubits"]
Didot	Quantity["DidotPoints"]
DidotPoint	Quantity["DidotPoints"]
Diopter	Quantity["Diopters"]
Ell	Quantity["Ells"]
Fathom	Quantity["Fathoms"]
Feet	Quantity["Feet"]
Fermi	Quantity["Fermis"]
Foot	Quantity["Feet"]
Furlong	Quantity["Furlongs"]
Hand	Quantity["HandsUnit"]
Inch	Quantity["Inches"]
Kayser	Quantity["Kaysers"]
League	Quantity["Leagues"]
LightYear	Quantity["LightYears"]
Link	Quantity["GuntersLinks"]
Meter	Quantity["Meters"]
Micron	Quantity["Microns"]
Mil	Quantity["Mils"]
Mile	Quantity["Miles"]
NauticalMile	Quantity["NauticalMiles"]
Parsec	Quantity["Parsecs"]
Perch	Quantity["PerchesLength"]
Pica	Quantity["Picas"]
Pole	Quantity["Poles"]
PrintersPoint	Quantity["DesktopPublishingPoints"]
Rod	Quantity["Rods"]
Rope	Quantity["Ropes"]
Skein	Quantity["Skeins"]
Stadion	Quantity["GreekStadions"]
Stadium	Quantity["StadiaCommon"]
StatuteMile	Quantity["Miles"]
SurveyMile	Quantity["SurveyMiles"]
XUnit	Quantity["XUnits"]
Yard	Quantity["Yards"]

質量と重量の単位

Units`	バージョン9
AMU	Quantity["AtomicMassUnit"]
AssayTon	Quantity["AssayShortTons"]
AtomicMassUnit	Quantity["AtomicMassUnit"]
AvoirdupoisOunce	Quantity["Ounces"]
AvoirdupoisPound	Quantity["Pounds"]
Bale	Quantity["BalesOfCotton"]
Carat	Quantity["Carats"]
Cental	Quantity["Centals"]
Dalton	Quantity["Daltons"]
Drachma	Quantity["AtticDrachmes"]
Geepound	Quantity["GeepoundsMass"]
Grain	Quantity["Grains"]
Gram	Quantity["Grams"]
GrossHundredweight	Quantity["LongHundredweights"]
Hundredweight	Quantity["LongHundredweights"]
Kilogram	Quantity["Kilograms"]
Libra	Quantity["RomanLibras"]
LongTon	Quantity["LongTons"]
MetricTon	Quantity["MetricTons"]
Mina	Quantity["AtticMinas"]
NetHundredweight	Quantity["ShortHundredweights"]
Obolos	Quantity["AtticObols"]
Ounce	Quantity["Ounces"]
Pennyweight	Quantity["Pennyweights"]
Pondus	Quantity["DutchPonds"]
Pound	Quantity["Pounds"]
Quintal	Quantity["Quintals"]
Shekel	Quantity["ShekelsMass"]
ShortHundredweight	Quantity["ShortHundredweights"]
ShortTon	Quantity["ShortTons"]
Slug	Quantity["SlugsMass"]
SolarMass	Quantity["SolarMass"]
Stone	Quantity["Stones"]
Talent	Quantity["GreekTalents"]
Ton	Quantity["ShortTons"]
Tonne	Quantity["MetricTons"]
TroyOunce	Quantity["TroyOunces"]

温度の単位

Units`	バージョン9
Celsius	Quantity["DegreesCelsius"] Quantity["DegreesCelsiusDifference"]
Centigrade	Quantity["DegreesCelsius"] Quantity["DegreesCelsiusDifference"]
Fahrenheit	Quantity["DegreesFahrenheit"] Quantity["DegreesFahrenheitDifference"]
Kelvin	Quantity["Kelvins"] Quantity["KelvinsDifference"]
Rankine	Quantity["DegreesRankine"] Quantity["DegreesRankineDifference"]

温度の単位には絶対温度と温度差の両方が含まれており，これらは異なる単位として扱われる．詳細はチュートリアル「温度単位」をご覧いただきたい．

体積の単位

Units`	バージョン9
Bag	Quantity["BagsUS"]
Barrel	Quantity["BarrelsOfOil"]
BoardFoot	Quantity["BoardFeet"]
Bucket	Quantity["BucketsUS"]
Bushel	Quantity["BushelsUS"]
Butt	Quantity["ButtsUS"]
Cord	Quantity["Cords"]
Ephah	Quantity["Ephahs"]
Fifth	Quantity["Fifths"]
Firkin	Quantity["FirkinsUS"]
FluidDram	Quantity["FluidDrams"]
FluidOunce	Quantity["FluidOunces"]
Gallon	Quantity["Gallons"]
Gill	Quantity["Gills"]
Hogshead	Quantity["HogsheadsUS"]
ImperialGallon	Quantity["GallonsUK"]
ImperialPint	Quantity["PintsUK"]
Jeroboam	Quantity["Jeroboams"]
Jigger	Quantity["Jiggers"]
Liter	Quantity["Liters"]
Magnum	Quantity["Magnums"]
Minim	Quantity["MinimsUS"]
Noggin	Quantity["NogginsUS"]
Omer	Quantity["Omers"]
Peck	Quantity["Pecks"]
Pint	Quantity["Pints"]
Pony	Quantity["PoniesUS"]
Puncheon	Quantity["PuncheonsUS"]
Quart	Quantity["Quarts"]
RegisterTon	Quantity["RegisterTon"]
Seam	Quantity["SeamsUS"]
Shot	Quantity["Shots"]
Stere	Quantity["Steres"]
Tablespoon	Quantity["Tablespoons"]
Teaspoon	Quantity["Teaspoons"]
Tun	Quantity["Tuns"]
UKGallon	Quantity["GallonsUK"]
UKPint	Quantity["PintsUK"]
WineBottle	Quantity["WineBottle750Milliliter"]

面積の単位

Units`	バージョン9
Acre	Quantity["Acres"]
Are	Quantity["Ares"]
Barn	Quantity["Barns"]
Hectare	Quantity["Hectares"]
Rood	Quantity["ScottishRods"]
Section	Quantity["SectionsArea"]
Township	Quantity["Townships"]

時間の単位

Units`	バージョン9
Century	Quantity["Centuries"]
Day	Quantity["Days"]
Decade	Quantity["Decades"]
Fortnight	Quantity["Fortnights"]
Hour	Quantity["Hours"]
Millennium	Quantity["Millennia"]
Minute	Quantity["Minutes"]
Month	Quantity["Months"]
Second	Quantity["Seconds"]
SiderealSecond	Quantity["SiderealSeconds"]
SiderealYear	Quantity["SiderealYears"]
TropicalYear	Quantity["TropicalYears"]
Week	Quantity["Weeks"]
Year	Quantity["Years"]

力，エネルギー，仕事率の単位

Units`	バージョン9
BritishThermalUnit	Quantity["BritishThermalUnitsIT"]
BTU	Quantity["BritishThermalUnitsIT"]
Calorie	Quantity["LargeCalories"]
ChevalVapeur	Quantity["ChevalVapeurs"]
Dyne	Quantity["Dynes"]
ElectronVolt	Quantity["Electronvolts"]
Erg	Quantity["Ergs"]
GramWeight	Quantity["GramsForce"]
Horsepower	Quantity["HorsepowerMechanical"]
Joule	Quantity["Joules"]
KilogramForce	Quantity["KilogramsForce"]
KilogramWeight	Quantity["KilogramWeight"]
Newton	Quantity["Newtons"]
Poundal	Quantity["Poundals"]
PoundForce	Quantity["PoundsForce"]
PoundWeight	Quantity["PoundsForce"]
Rydberg	Quantity["Rydbergs"]
Therm	Quantity["Therms"]
TonForce	Quantity["LongTonsForce"]
Watt	Quantity["Watts"]

圧力の単位

Units`	バージョン9
Atmosphere	Quantity["Atmospheres"]
Bar	Quantity["Bars"]
Barye	Quantity["Baryes"]
InchMercury	Quantity["InchesOfMercury"]
MillimeterMercury	Quantity["MillimetersOfMercury"]
Pascal	Quantity["Pascals"]
PoundsPerSquareInch	Quantity["PoundsForce"/"Inches"^2]
PSI	Quantity["PoundsForce"/"Inches"^2]
Torr	Quantity["Torr"]

電磁気の単位

Units`	バージョン9
Abampere	Quantity["ABAmperes"]
Abcoulomb	Quantity["ABCoulombs"]
Abfarad	Quantity["ABFarads"]
Abhenry	Quantity["ABHenries"]
Abmho	Quantity["ABMhos"]
Abohm	Quantity["ABOhms"]
Abvolt	Quantity["ABVolts"]
Amp	Quantity["Amperes"]
Ampere	Quantity["Amperes"]
Biot	Quantity["Biots"]
BohrMagneton	Quantity["BohrMagneton"]
Coulomb	Quantity["Coulombs"]
Farad	Quantity["Farads"]
Gauss	Quantity["Gausses"]
Gilbert	Quantity["Gilberts"]
Henry	Quantity["Henries"]
Maxwell	Quantity["Maxwells"]
Mho	Quantity["Mhos"]
NuclearMagneton	Quantity["NuclearMagnetons"]
Oersted	Quantity["Oersteds"]
Ohm	Quantity["Ohms"]
Siemens	Quantity["Siemens"]
Statampere	Quantity["StatAmperes"]
Statcoulomb	Quantity["StatCoulombs"]
Statfarad	Quantity["StatFarads"]
Stathenry	Quantity["StatHenries"]
Statohm	Quantity["StatOhms"]
Statvolt	Quantity["StatVolts"]
Tesla	Quantity["Teslas"]
Volt	Quantity["Volts"]
Weber	Quantity["Webers"]

照度の単位

Units`	バージョン9
Apostilb	Quantity["Apostilbs"]
Candela	Quantity["Candelas"]
Candle	Quantity["Candle"]
FootCandle	Quantity["FootCandle"]
Hefner	Quantity["HefnerKerzen"]
Lambert	Quantity["Lamberts"]
Lumerg	Quantity["Lumergs"]
Lumen	Quantity["Lumens"]
Lux	Quantity["Lux"]
Nit	Quantity["Nits"]
Phot	Quantity["Phots"]
Stilb	Quantity["Stilbs"]
Talbot	Quantity["Talbots"]

情報の単位

Units`	バージョン9
Baud	Quantity["Bits"/"Seconds"]
Bit	Quantity["Bits"]
Nibble	Quantity["Nibbles"]

放射能の単位

Units`	バージョン9
Becquerel	Quantity["Becquerels"]
Curie	Quantity["Curies"]
GrayDose	Quantity["Grays"]
Rad	Quantity["Rads"]
Roentgen	Quantity["Roentgens"]
Rontgen	Quantity["Roentgens"]
Rutherford	Quantity["Rutherfords"]

粘度の単位

Units`	バージョン9
Poise	Quantity["Poise"]
Reyn	Quantity["Reyns"]
Rhes	Quantity["Rhes"]
Stokes	Quantity["Stokes"]

単位乗数

Units`	バージョン9
ArcMinute	Quantity["ArcMinutes"]
ArcSecond	Quantity["ArcSeconds"]
BakersDozen	Quantity["BakersDozens"]
Dozen	Quantity["Dozens"]
Grade	Quantity["Grads"]
Gross	Quantity["Grosses"]
Percent	Quantity["Percent"]
Quadrant	Quantity[π/2,"Radians"]
RightAngle	Quantity["RightAngles"]

その他の単位

Units`	バージョン9
Denier	Quantity["Denier"]
Gal	Quantity["Galileos"]
Gravity	Quantity["StandardAccelerationOfGravity"]
Hertz	Quantity["Hertz"]
Knot	Quantity["Knots"]
Mole	Quantity["Moles"]
Radian	Quantity["Radians"]
Steradian	Quantity["Steradians"]

カーネルの単位は，複数形の文字列で表されることに特に注意すること．

無次元単位における単位のない形式は，単位として1を使って導くことができる．

上記の変換による値の中には，以前のパッケージとはわずかに異なるものもある．それは，ハッブル定数のように，科学研究の進歩の結果によるためである場合もあれば，空気中における音速のように，値を導くために使われる標準が少し異なったためである場合もある．また，いわゆる太陽定数は，実際には定数ではないため例外であり，現在の値は太陽周期をより正しく反映している．