The quick answer

An A record points a hostname to an IPv4 address; an AAAA record points it to an IPv6 address. A CNAME makes one hostname an alias of another. Use the exact record type and value your website host supplies for the address you are connecting.

Three differently shaped keys fit matching sockets on a server.
AI-generated editorial illustration for NameUK.

Before you begin

  • Use the host’s exact record type.
  • Check root and www separately.
  • Do not add unsupported IPv6 records.

Match the value to the record type

An A record needs an IPv4 address, while an AAAA record needs an IPv6 address. A CNAME target is another hostname. Do not paste a complete web address with https:// or a page path into those fields.

The record name also matters. Your DNS editor may use @ or a blank name for the root, and www for the common subdomain. Check its convention so a copied full hostname does not accidentally acquire the domain suffix twice.

Treat root and www separately

A host may request an A record at the root and a CNAME for www, or another supported arrangement. Follow the instructions for the actual account. Making one hostname work does not automatically configure the other in DNS or on the website server.

A conventional CNAME cannot coexist with other record types at the same name, which creates a particular issue at a zone’s root. Some providers offer alias or flattening features. Do not assume every DNS editor supports those features or convert a host’s instructions on your own.

Check before deleting old records

Only remove or replace records whose purpose you understand.

  • Confirm the requested hostname, record type and value.
  • Check for an older A or AAAA answer that points elsewhere.
  • Preserve MX, TXT and unrelated application records.
  • Review whether the website host supports IPv6 before adding AAAA.
  • Test the final authoritative answers and the website response.

A correct DNS answer is only one step

The destination host must be configured to serve your domain and provide HTTPS for it. If DNS points at the correct service but the browser shows an unknown-site message, inspect the hosting setup before changing the address again.

For domains delegated to an external DNS host, make these changes there. NameUK’s registrar dashboard remains the place to manage the registration, supported nameserver changes and renewals, while the active DNS provider supplies the records.

Prepared with AI-assisted drafting and illustration, then checked against the linked sources and NameUK’s current service. The artwork is conceptual; setup values must come from your own provider.

Further readingCloudflare: DNS A records ↗Cloudflare: DNS AAAA records ↗Cloudflare: DNS CNAME records ↗NameUK registration and renewal prices ↗

Extension rules and provider processes can change. Check the current registrar instructions before a registration, transfer or renewal.

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