---
title: blur
summary: null
url: https://www.fastly.com/documentation/reference/io/blur
---

Applies a [Gaussian blur](https://en.wikipedia.org/wiki/Gaussian_blur) filter to the image.

## Syntax

```text
blur={value}
```

`{value}` is a number of pixels between 0.5 and 1000 or a percentage (of the dimensions of the image) suffixed with `p` (e.g., `1p` for 1%).

## Examples

Click the links to view the transformed image using a demo Fastly IO service.

| Example usage                                             | Description                                                   |
| --------------------------------------------------------- | ------------------------------------------------------------- |
| [`?blur=50`](https://www.fastly.io/image.jpg?blur=50)     | Apply a Gaussian blur with a radius of 50px                   |
| [`?blur=0.5p`](https://www.fastly.io/image.jpg?blur=0.5p) | Apply a Gaussian blur with a radius of 0.5% of the image size |