---
title: 'previewBody'
sidebar:
  order: 16
  title: previewBody
---

Parent: [main.js|ts configuration](./main-config.mdx)

Type: `(body: string) => string`

Programmatically adjust the [preview `<body>`](../../configure/story-rendering.mdx#adding-to-body) of your Storybook. Most often used by [addon authors](../../addons/writing-presets.mdx#ui-configuration).

<Callout variant="info" icon="💡">

  If you don't need to programmatically adjust the preview body, you can add scripts and styles to [`preview-body.html`](../../configure/story-rendering.mdx#adding-to-body) instead.
  
</Callout>

For example, you can conditionally add scripts or styles, depending on the environment:

{/* prettier-ignore-start */}

<CodeSnippets path="main-config-preview-body.md" />

{/* prettier-ignore-end */}
