# SwiftUI forms: Slider

> Learn how to use the Slider control in SwiftUI to let users drag to pick a value, setting its value, in range, and step parameters to control the range.

Author: [Flavio Copes](https://flaviocopes.com/about/) | Published: 2021-09-28 | Topics: [Swift](https://flaviocopes.com/tags/swift/) | Canonical: https://flaviocopes.com/swiftui-forms-slider/

The `Slider` form control in SwiftUI lets us create a bar that the user can swipe left or right to decrease or increase its value.

We initialize a Slider by setting 3 parameters: `value`, `in`, `step`:

```swift
@State private var age: Double = 0

//...

Slider(value: $age, in: 0...100, step: 1)
```

`in` limits the minimum and maximum values we can use.

`step` means we can step by a value of 1 at a time, in this case we can go from 0 to 1 to 2 etc. You could use 10, or 0.2, and so on. 

Since `Slider` takes a `Double` value, by default we increment the decimals too.

Example:

```swift
struct ContentView: View {
    @State private var age: Double = 0
    
    var body: some View {
        Form {
            Slider(value: $age, in: 0...100, step: 1)
            Text("\(age)")
        }
    }
}
```

![iPhone simulator showing SwiftUI form with slider at minimum position displaying value 0.000000](https://flaviocopes.com/images/swiftui-forms-slider/Screen_Shot_2021-09-23_at_19.30.44.png)

![iPhone simulator showing SwiftUI form with slider partially moved displaying value 34.000000](https://flaviocopes.com/images/swiftui-forms-slider/Screen_Shot_2021-09-23_at_19.30.46.png)

Notice how I added a `Text` view to show the value of `age`. 

Since it's a double, we have lots of decimals.

We could format that, but for this we'll have another post.