ConfigurationCustomize branding

Bring your custom domain

Bring Fern Docs to your custom domain.

You can use:

  • A custom domain, such as example.com
  • A subdomain on your custom domain, such as docs.example.com
  • A subpath on your custom domain, such as example.com/docs
This feature is available on the Starter plan and above. Want to get set up? Reach out in Discord or email us.

Steps

Step 1: Open docs.yml

Open the docs.yml file, which lives in the fern/ folder of your Fern Docs repository.

No Fern Docs repository yet? Use our Fern Docs Quickstart to set up your starter site, then return to this page.

Step 2: Configure the url

The subdomain of the url under instances must match your custom domain. If you want to use a custom domain of example.com, the subdomain must be example, as shown below:

docs.yml example
1instances:
2 - url: example.docs.buildwithfern.com

Leave the .docs.buildwithfern.com part of the url unchanged.

If you intend to use a subpath with your custom domain, such as example.com/docs, append that subpath to the end of the url:

docs.yml example for subpath
1instances:
2 - url: example.docs.buildwithfern.com/docs

Step 3: Configure the custom-domain

Below the url, add a custom-domain key as shown in the examples below.

The examples use docs for the subdomain and subpath specified in custom-domain, but you can use any word you like, such as reference or learn.
1instances:
2 - url: example.docs.buildwithfern.com
3 custom-domain: docs.example.com

Step 4: Update the Fern Docs site

If you created your Fern Docs site using one of our Docs Quickstarts, push the changes you made to your GitHub repository. This runs a GitHub Action to update the site with your new configuration.

If you need to update your Fern Docs site manually, run fern generate --docs.

Step 5: Create DNS records to point at Fern Docs

This feature is available on the Fern Docs Starter plan and above. Reach out to sales@buildwithfern.com to set up your subscription and obtain DNS records information for your domain registrar.