Alternate Domains

Read the Docs supports a number of custom domains for your convenience. Shorter urls make everyone happy, and we like making people happy!

Subdomain Support

Every project has a subdomain that is available to serve its documentation. If you go to <slug>, it should show you the latest version of documentation. A good example is


If you have an old project that has an underscore (_) in the name, it will use a subdomain with a hyphen (-). RFC 1035 has more information on valid subdomains.

CNAME Support

If you have your own domain, you can still host with us. This requires two steps:

  • Add a CNAME record in your DNS that point to our servers
  • Add a Domain object in the Project Admin > Domains page for your project.

Using pip as an example, resolves, but is hosted on our infrastructure.

As an example, fabric’s dig record looks like this:

-> dig


We used to map your projects documentation from the subdomain that you pointed your CNAME to. This wasn’t workable at scale, and now we require you to set the domain you want to resolve on your project.


We don’t support SSL for CNAMEs on our side, but you can enable support if you have your own server. SSL requires having a secret key, and if we hosted the key for you, it would no longer be secret.

To enable SSL:

  • Have a server listening on 443 that you control
  • Add a domain that you wish to point at Read the Docs
  • Enable proxying to us, with a custom X-RTD-SLUG header

An example nginx configuration for pip would look like:

 server {
     location / {
         proxy_set_header Host $http_host;
         proxy_set_header X-Forwarded-Proto https;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Scheme $scheme;
         proxy_set_header X-RTD-SLUG pip;
         proxy_connect_timeout 10s;
         proxy_read_timeout 20s;

You can also use and for short URLs for Read the Docs. For example, redirects to its documentation page. Any use of or will simply be redirected to