URL Record Format and Technical Details

This document serves as a reference for the structure and underlying technical implementation of DNSimple’s proprietary URL record type. This record type facilitates web (HTTP/HTTPS) redirects directly through DNSimple’s services.

URL record format

The URL record is a special record type developed by DNSimple and is not defined by any standard RFC. Its functionality is proprietary to DNSimple’s name servers and redirector service.

In DNSimple’s record editor, the URL record is represented by the following configurable elements:

Element	Description	Constraints & Details
Name	The hostname for the record, without the domain name. Generally referred to as the “subdomain” (e.g., www, blog). DNSimple automatically appends your domain name.	Cannot be blank if setting up a subdomain. If setting up a redirect for the apex domain (e.g., `example.com`), leave this field blank.
TTL	The time-to-live in seconds. This is the amount of time the record is allowed to be cached by a DNS resolver.	An unsigned 32-bit integer. Standard DNS TTL values apply.
URL	The full destination URL to which the source hostname should redirect.	Must be a valid, complete URL including the scheme (e.g., `https://www.example.com/new-page`).

Technical implementation: how DNSimple exposes URL records

You configure a URL record in the DNSimple interface, and DNSimple handles its technical implementation at the DNS level. The URL record itself does not exist as a standard DNS record type that is directly served to clients.

Instead, when you create a URL record:

Underlying A and AAAA records: DNSimple automatically configures a set of standard A (IPv4) and AAAA (IPv6) records for the source hostname (e.g., www.yourdomain.com) to point to the IP addresses of DNSimple’s redirector service.
HTTP/HTTPS redirect service: When an HTTP/HTTPS client (like a web browser) attempts to access the source hostname, its DNS query resolves to one of our redirector service’s IP addresses. The redirector service then receives the HTTP/HTTPS request.
Redirect response: Our redirector service then serves an appropriate HTTP/HTTPS redirect response (e.g., a 301 Moved Permanently) to the client. This response includes the Location header, which contains the target URL you specified in the URL record.
Client follows redirect: The client’s web browser then automatically follows this HTTP/HTTPS redirect to the final target URL.

From the perspective of a querying DNS resolver, the source hostname appears to have standard A and AAAA records pointing to DNSimple’s infrastructure. The web redirection itself occurs at the HTTP/HTTPS layer, handled by DNSimple’s servers.

Have more questions?

If you have additional questions or need any assistance with your URL records, just contact support, and we’ll be happy to help.