---
title: fillOpacity
framework: mapkitjs
role: symbol
role_heading: Interface Property
path: mapkitjs/styleconstructoroptions/fillopacity
---

# fillOpacity

The opacity of the fill color.

## Declaration

```data
fillOpacity?: number;
```

## Discussion

Discussion The value of this property can be in the range of 0 (fully transparent) to 1 (fully opaque). The default fill opacity is 0.1.

## See Also

### Setting fill styles

- [fillColor](mapkitjs/styleconstructoroptions/fillcolor.md)
- [fillRule](mapkitjs/styleconstructoroptions/fillrule.md)