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# firstDayOfWeek

The first day of the week as represented by this locale.

```
var firstDayOfWeek: Locale.Weekday { get }
```

## Discussion

This value is the preferred first day of the week to show in a calendar view. It isn’t necessarily the same as the first day after the weekend; don’t try to determine a first-day-of-week value from weekend information.

This property corresponds to the `fw` key of the Unicode BCP 47 extension.

For locale instances created with the `fw` specifier (such as `en-US@fw=mon`), or with a custom [`Locale.Components`](/documentation/Foundation/Locale/Components), this property represents the custom day. Otherwise, it represents the locale’s default first day of the week.

---

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