---
title: "How To Create Custom Fields During App Installation\n"
space: "Framework"
url: "https://docs.frappe.io/framework/user/en/guides/app-development/how-to-create-custom-fields-during-app-installation"
updated: "2026-02-17"
---


Your custom app can automatically add **Custom Fields** to DocTypes outside of your app when it is installed to a new site.

To do this, add the new custom fields that your app requires, using the Frappe web application.

In your `hooks.py` file, add `"Custom Fields"`

 fixtures = ["Custom Field"]

Export fixtures before you commit your app with:

 $ bench --site mysite export-fixtures

This will create a new folder called `fixtures` in your app folder and a `.csv` or `.json` file will be created with the definition of the custom fields you added.

This file will be automatically imported when the app is installed in a new site or updated via `bench update`.

Note: You can also add single DocTypes like "Website Settings" as fixtures