# Blur comparison

The left circle has no filter. The right circle has `blur({ radius: 8 })`. Both have radius 60 and fill `#267d7c`; only the pixels differ. The preview uses a 600 by 200 logical surface.

```js
import { blur } from '@pibbl/core/filters';
// On the right circle:
style: { cx: 450, cy: 100, radius: 60, fill: '#267d7c',
  filter: [blur({ radius: 8 })] }
```

Notice the softened edge. Blur does not enlarge the circle's hit geometry or layout box. A filter on a parent combines that primitive and its descendants, so moving the boundary changes the result.

[Full blur reference](/reference/blur/) · [Open editable filters](/playground/#/examples/drawing/filters) · [Composition boundaries](/guides/foundations/)

## Documentation version

Documentation built with @pibbl/core 0.0.2, revision 272a94a. ALPHA — NOT FOR PRODUCTION USE.