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# UnitVolume

A unit of measure for volume.

```
class UnitVolume
```

## Overview

You typically use instances of [`UnitVolume`](/documentation/Foundation/UnitVolume) to represent specific quantities of volume using the [`NSMeasurement`](/documentation/Foundation/NSMeasurement) class.

### Volume

Volume is a quantity of the extend of matter in three dimensions. The SI accepted unit of volume is the liter (L), which is derived as one cubic decimeter (1 dm3). Volume is also commonly expressed in terms of cubic meters (m3), gallons (gal), and cups (cup).

The [`UnitVolume`](/documentation/Foundation/UnitVolume) class defines its [`baseUnit()`](/documentation/Foundation/Dimension/baseUnit()) as [`liters`](/documentation/Foundation/UnitVolume/liters), and provides the following units, which are initialized using [`UnitConverterLinear`](/documentation/Foundation/UnitConverterLinear) converters with the specified coefficients:

|Name                 |Method                                                                                |Symbol    |Coefficient |
|---------------------|--------------------------------------------------------------------------------------|----------|------------|
|Megaliters           |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/megaliters``         |ML        |`1000000.0` |
|Kiloliters           |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/kiloliters``         |kL        |`1000.0`    |
|Liters               |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/liters``             |L         |`1.0`       |
|Deciliters           |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/deciliters``         |dL        |`0.1`       |
|Centiliters          |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/centiliters``        |cL        |`0.01`      |
|Milliliters          |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/milliliters``        |mL        |`0.001`     |
|Cubic Kilometers     |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicKilometers``    |km³       |`1e12`      |
|Cubic Meters         |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicMeters``        |m³        |`1000.0`    |
|Cubic Decimeters     |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicDecimeters``    |dm³       |`1.0`       |
|Cubic Centimeters    |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicCentimeters``   |cm³       |`0.001`     |
|Cubic Millimeters    |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicMillimeters``   |mm³       |`0.000001`  |
|Cubic Inches         |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicInches``        |in³       |`0.0163871` |
|Cubic Feet           |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicFeet``          |ft³       |`28.3168`   |
|Cubic Yards          |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicYards``         |yd³       |`764.555`   |
|Cubic Miles          |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cubicMiles``         |mi³       |`4.168e+12` |
|Acre Feet            |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/acreFeet``           |af        |`1.233e+6`  |
|Bushels              |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/bushels``            |bsh       |`35.2391`   |
|Teaspoons            |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/teaspoons``          |tsp       |`0.00492892`|
|Tablespoons          |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/tablespoons``        |tbsp      |`0.0147868` |
|Fluid Ounces         |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/fluidOunces``        |fl oz     |`0.0295735` |
|Cups                 |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/cups``               |cup       |`0.24`      |
|Pints                |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/pints``              |pt        |`0.473176`  |
|Quarts               |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/quarts``             |qt        |`0.946353`  |
|Gallons              |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/gallons``            |gal       |`3.78541`   |
|Imperial Teaspoons   |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/imperialTeaspoons``  |tsp       |`0.00591939`|
|Imperial Tablespoons |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/imperialTablespoons``|tbsp      |`0.0177582` |
|Imperial Fluid Ounces|``doc://com.apple.foundation/documentation/Foundation/UnitVolume/imperialFluidOunces``|fl oz     |`0.0284131` |
|Imperial Pints       |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/imperialPints``      |pt        |`0.568261`  |
|Imperial Quarts      |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/imperialQuarts``     |qt        |`1.13652`   |
|Imperial Gallons     |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/imperialGallons``    |gal       |`4.54609`   |
|Metric Cups          |``doc://com.apple.foundation/documentation/Foundation/UnitVolume/metricCups``         |metric cup|`0.25`      |

## Topics

### Accessing the Base Unit

[`baseUnit()`](/documentation/Foundation/Dimension/baseUnit())

Returns the base unit.

### Accessing Predefined Units

[`megaliters`](/documentation/Foundation/UnitVolume/megaliters)

The megaliters unit of volume.

[`kiloliters`](/documentation/Foundation/UnitVolume/kiloliters)

The kiloliters unit of volume.

[`liters`](/documentation/Foundation/UnitVolume/liters)

The liters unit of volume.

[`deciliters`](/documentation/Foundation/UnitVolume/deciliters)

The deciliters unit of volume.

[`centiliters`](/documentation/Foundation/UnitVolume/centiliters)

The centiliters unit of volume.

[`milliliters`](/documentation/Foundation/UnitVolume/milliliters)

The milliliters unit of volume.

[`cubicKilometers`](/documentation/Foundation/UnitVolume/cubicKilometers)

The cubic kilometers unit of volume.

[`cubicMeters`](/documentation/Foundation/UnitVolume/cubicMeters)

The cubic meters unit of volume.

[`cubicDecimeters`](/documentation/Foundation/UnitVolume/cubicDecimeters)

The cubic decimeters unit of volume.

[`cubicCentimeters`](/documentation/Foundation/UnitVolume/cubicCentimeters)

The cubic centimeters unit of volume.

[`cubicMillimeters`](/documentation/Foundation/UnitVolume/cubicMillimeters)

The cubic millimeters unit of volume.

[`cubicInches`](/documentation/Foundation/UnitVolume/cubicInches)

The cubic inches unit of volume.

[`cubicFeet`](/documentation/Foundation/UnitVolume/cubicFeet)

The cubic feet unit of volume.

[`cubicYards`](/documentation/Foundation/UnitVolume/cubicYards)

The cubic yards unit of volume.

[`cubicMiles`](/documentation/Foundation/UnitVolume/cubicMiles)

The cubic miles unit of volume.

[`acreFeet`](/documentation/Foundation/UnitVolume/acreFeet)

The acre feet unit of volume.

[`bushels`](/documentation/Foundation/UnitVolume/bushels)

The bushels unit of volume.

[`teaspoons`](/documentation/Foundation/UnitVolume/teaspoons)

The teaspoons unit of volume.

[`tablespoons`](/documentation/Foundation/UnitVolume/tablespoons)

The tablespoons unit of volume.

[`fluidOunces`](/documentation/Foundation/UnitVolume/fluidOunces)

The fluid ounces unit of volume.

[`cups`](/documentation/Foundation/UnitVolume/cups)

The cups unit of volume.

[`pints`](/documentation/Foundation/UnitVolume/pints)

The pints unit of volume.

[`quarts`](/documentation/Foundation/UnitVolume/quarts)

The quarts unit of volume.

[`gallons`](/documentation/Foundation/UnitVolume/gallons)

The gallons unit of volume.

[`imperialTeaspoons`](/documentation/Foundation/UnitVolume/imperialTeaspoons)

The imperial teaspoons unit of volume.

[`imperialTablespoons`](/documentation/Foundation/UnitVolume/imperialTablespoons)

The imperial tablespoons unit of volume.

[`imperialFluidOunces`](/documentation/Foundation/UnitVolume/imperialFluidOunces)

The imperial fluid ounces unit of volume.

[`imperialPints`](/documentation/Foundation/UnitVolume/imperialPints)

The imperial pints unit of volume.

[`imperialQuarts`](/documentation/Foundation/UnitVolume/imperialQuarts)

The imperial quarts unit of volume.

[`imperialGallons`](/documentation/Foundation/UnitVolume/imperialGallons)

The imperial gallons unit of volume.

[`metricCups`](/documentation/Foundation/UnitVolume/metricCups)

The metric cups unit of volume.


---

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