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# MassFormatter

A formatter that provides localized descriptions of mass and weight values.

```
class MassFormatter
```

## Overview> Note:
> As of iOS 10, macOS 10.12, tvOS 10, and watchOS 3, Foundation provides the ``doc://com.apple.foundation/documentation/Foundation/MeasurementFormatter`` class, which can be used to represent quantities of ``doc://com.apple.foundation/documentation/Foundation/UnitMass`` to provide equivalent functionality to ``doc://com.apple.foundation/documentation/Foundation/MassFormatter``. You are encouraged to transition to these new Foundation Units and Measurements APIs whenever possible.

## Topics

### Formatting Mass Strings

[`isForPersonMassUse`](/documentation/Foundation/MassFormatter/isForPersonMassUse)

A Boolean value that indicates whether the resulting string represents a person’s mass.

[`getObjectValue(_:for:errorDescription:)`](/documentation/Foundation/MassFormatter/getObjectValue(_:for:errorDescription:))

This method is not supported for the `NSMassFormatter` class.

[`numberFormatter`](/documentation/Foundation/MassFormatter/numberFormatter)

The number formatter used to format the numbers in a mass strings.

[`string(fromKilograms:)`](/documentation/Foundation/MassFormatter/string(fromKilograms:))

Returns a mass string for the provided value.

[`string(fromValue:unit:)`](/documentation/Foundation/MassFormatter/string(fromValue:unit:))

Returns a properly formatted mass string for the given value and unit.

[`unitString(fromKilograms:usedUnit:)`](/documentation/Foundation/MassFormatter/unitString(fromKilograms:usedUnit:))

Returns the unit string for the provided value.

[`unitString(fromValue:unit:)`](/documentation/Foundation/MassFormatter/unitString(fromValue:unit:))

Returns the unit string based on the provided value and unit.

[`unitStyle`](/documentation/Foundation/MassFormatter/unitStyle)

The unit style used by this formatter.

### Constants

[`MassFormatter.Unit`](/documentation/Foundation/MassFormatter/Unit)

The units supported by the `NSMassFormatter` class.


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