Choosing a subdomain

Please follow the steps to set a custom domain in this order:
Only subdomains can be used to serve your GitBook documentation. It's not possible to use an apex domain.
Here are some examples of what you could and could not choose — just replace with your own domain:
Domain type
Apex domain
www subdomain
Custom subdomain
Once you have chosen your custom domain, you're ready to move onto the next step: deciding where to set the custom domain.