---
title: alpha
framework: mapkit
role: symbol
role_heading: Instance Property
path: mapkit/mkoverlayrenderer/alpha
---

# alpha

The amount of transparency to apply to the overlay.

## Declaration

```swift
var alpha: CGFloat { get set }
```

## Discussion

Discussion The value in this property can be in the range 0.0 to 1.0, where 0.0 represents total transparency and 1.0 represents total opacity. The default value of this property is 1.0.

## See Also

### Attributes of the overlay

- [overlay](mapkit/mkoverlayrenderer/overlay.md)
- [contentScaleFactor](mapkit/mkoverlayrenderer/contentscalefactor.md)
- [blendMode](mapkit/mkoverlayrenderer/blendmode.md)