CNAME flattening was popularized in part by Cloudflare.
We have used CNAME flattening successfully with multiple web-hosting providers.
For the layperson, DNS A records are a pre-WWW artifact necessary to resolve the apex domain
You may see some old 2014 blog posts initially complaining about the idea of CNAME flattening, citing some initial hiccups that have long since been resolved.
Implement CNAME flattening
To enable CNAME flattening with your DNS records, first screenshot or otherwise backup your DNS settings. Don’t do this experiment during busy times, better to use on a little-used or test website first to ensure it works correctly with your complete setup.
- Determine the web address your web hosting provider puts your website at. E.g. for GitHub Pages it would be
- Remove DNS
example.comthat points to a specific IP address
- Add a
example.comto the server address from step #1
For GitHub username
joe with GitHub Pages site at
joe.github.io, with desired web address
example.com: make a
CNAME DNS record with
example.com as an alias to
Cloudflare CNAME flattening article