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CNAME flattening

CNAME flattening speeds up CNAME resolution and allows you to use a CNAME record at your root/apex domain (example.com).

How it works

With CNAME flattening, Cloudflare finds the IP address that a CNAME points to. This process could involve a single lookup or multiple (if your CNAME points to another CNAME). Cloudflare then returns the final IP address instead of a CNAME record, helping DNS queries resolve up to 30% faster.

For more details on the mechanics of CNAME flattening, refer to the blog post.

Set up CNAME flattening

For your root domain

CNAME flattening occurs by default for all plans when your domain uses a CNAME record for its root domain (example.com).

For all CNAME records

Accounts on paid plans can also choose to flatten all CNAME records on their domain. This option is useful for DNS-only (unproxied) CNAME records since proxied records are flattened by default (as they return Cloudflare edge IPv4 and IPv6 addresses).

  1. Log in to the Cloudflare dashboard and select your account and domain.
  2. Navigate to DNS.
  3. For CNAME Flattening, select Flatten all CNAMEs.