---
title: measurementSystem
framework: foundation
role: symbol
role_heading: Instance Property
path: foundation/locale/components/measurementsystem
---

# measurementSystem

The measurement system used by the locale, like metric or the US system.

## Declaration

```swift
var measurementSystem: Locale.MeasurementSystem?
```

## Discussion

Discussion Set this property to override the locale’s default measurement system. To request the default measurement system used by the locale, use the Locale property measurementSystem. This property corresponds to the ms key of the Unicode BCP 47 extension.

## See Also

### Specifiying measurement and counting components

- [currency](foundation/locale/components/currency.md)
- [Locale.Currency](foundation/locale/currency-swift.struct.md)
- [Locale.MeasurementSystem](foundation/locale/measurementsystem-swift.struct.md)
- [numberingSystem](foundation/locale/components/numberingsystem.md)
- [Locale.NumberingSystem](foundation/locale/numberingsystem-swift.struct.md)