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


Allows SVG output images to scale beyond the specified width and height.

## Syntax

```text
viewbox={value}
```

## Allowed values

|Value  |Description|
|-------|-----------|
|`1`| Remove explicit `width` and `height` properties in the output image in favor of a single `viewBox` property. |

## Notes

1. This is useful when you have an SVG that you want rendered using relative sizes as opposed to an explicit width and height (for example, in a flexible layout). Using `viewbox` allows the rendered SVG to scale to fit the dimensions of the parent element on the page.
1. This parameter only works with `format=svg`. It is ignored when the format is set to anything else.

## Examples

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

|Example usage|Description|
|-----------|-------------|
|[`?format=svg&width=1000&viewbox=1`](https://www.fastly.io/wave.jpg?format=svg&width=1000&viewbox=1)|Resize the image to 1000px wide and render as an SVG using viewbox|