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CommonUnits[{quantity1,quantity2,…,quantityn}]

converts quantity1 through quantityn to common units across compatible dimensions.

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Basic Examples  
Scope  
Properties & Relations  
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CommonUnits

CommonUnits[{quantity1,quantity2,…,quantityn}]

converts quantity1 through quantityn to common units across compatible dimensions.

Details

  • CommonUnits will convert the input list's units to a common unit for each subset of input units with common dimensions.
  • CommonUnits uses heuristic methods to determine a unit that best fits the input data.
  • Operations involving currency units require internet connectivity.

Examples

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Basic Examples  (2)

Convert a list of lengths to a common unit:

Wolfram Language code: CommonUnits[{Quantity[2, "Feet"], Quantity[30, "Inches"], Quantity[0.25, "Meters"]}]

Convert all units of length and mass to a common unit:

Wolfram Language code: CommonUnits[{Quantity[10, "Feet"], Quantity[300, "Inches"], Quantity[45, "Pounds"], Quantity[12.2, "Kilograms"]}]

Scope  (4)

Use CommonUnits with a list of Quantity objects:

Wolfram Language code: CommonUnits[{Quantity[3.2, "Meters"], Quantity[10, "Inches"], Quantity[7, "Feet"]}]
Wolfram Language code: CommonUnits[{Quantity[3.5, "Kilograms"], Quantity[3.5, "ChineseJins"], Quantity[3.5, "Pounds"]}]

Use CommonUnits with a QuantityArray object:

Wolfram Language code: qa = QuantityArray[Transpose@{Range[100], Range[100]}, {"Meters", "Inches"}]
Wolfram Language code: CommonUnits[qa]

CommonUnits can convert quantities with IndependentUnit specifications:

Wolfram Language code: qa = Quantity[5, "Kilo"IndependentUnit["Apples"] / "Meters" ^ 2]
Wolfram Language code: qb = Quantity[300, IndependentUnit["Apples"] / "Feet" ^ 2]
Wolfram Language code: CommonUnits[{N[qa], qb}]

CommonUnits can convert mixed quantities:

Wolfram Language code: qa = Quantity[MixedMagnitude[{1, 80}], MixedUnit[{"Meters", "Centimeters"}]]
Wolfram Language code: qb = Quantity[MixedMagnitude[{5, 10}], MixedUnit[{"Feet", "Inches"}]]
Wolfram Language code: CommonUnits[{qa, N[qb]}]

Properties & Relations  (3)

CommonUnits converts quantities sharing the same UnitDimensions:

Wolfram Language code: CommonUnits[{Quantity[0.5, "Teslas"], Quantity[200, "Gausses"], Quantity[10, "Webers"/"Dekameters"^2]}]
Wolfram Language code: UnitDimensions /@ {Quantity[0.5, "Teslas"], Quantity[200, "Gausses"], Quantity[10, "Webers"/"Dekameters"^2]}

CommonUnits acts on subsets of quantities sharing the same UnitDimensions:

Wolfram Language code: CommonUnits[{Quantity[3., "Meters"/"Seconds"], Quantity[0.23, "Kilograms"], Quantity[40., "Miles"/"Hours"], Quantity[6.5, "Pounds"]}]
Wolfram Language code: GroupBy[{Quantity[3., "Meters"/"Seconds"], Quantity[0.23, "Kilograms"], Quantity[40., "Miles"/"Hours"], Quantity[6.5, "Pounds"]}, UnitDimensions]

CommonUnits converts quantities with dimensionless units to pure numbers:

Wolfram Language code: {Quantity[7, "Percent"], Quantity[3, "Dozens"], Quantity[34, "PartsPerMillion"]}
Wolfram Language code: %//CommonUnits
Wolfram Research (2012), CommonUnits, Wolfram Language function, https://reference.wolfram.com/language/ref/CommonUnits.html.

Text

Wolfram Research (2012), CommonUnits, Wolfram Language function, https://reference.wolfram.com/language/ref/CommonUnits.html.

CMS

Wolfram Language. 2012. "CommonUnits." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/CommonUnits.html.

APA

Wolfram Language. (2012). CommonUnits. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CommonUnits.html

BibTeX

@misc{reference.wolfram_2026_commonunits, author="Wolfram Research", title="{CommonUnits}", year="2012", howpublished="\url{https://reference.wolfram.com/language/ref/CommonUnits.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_commonunits, organization={Wolfram Research}, title={CommonUnits}, year={2012}, url={https://reference.wolfram.com/language/ref/CommonUnits.html}, note=[Accessed: 13-June-2026]}