A Complete Guide to DNS Records (A, AAAA, CNAME, MX, TXT and More)

DNS — the Domain Name System — is the internet's address book. It translates a human-friendly name like yourdomain.com into the machine addresses browsers and mail servers actually connect to. Understanding the handful of record types below makes almost every hosting task clearer, from launching a site to fixing email.

How a lookup works

When someone visits your site, their computer asks a DNS resolver "what is the address for yourdomain.com?" The resolver walks up the chain to the servers responsible for your domain (its nameservers) and returns the answer. Results are cached for a period set by each record's TTL (time to live), which is why changes are not always instant.

The record types you will actually use

• A record — points a name to an IPv4 address (for example @ and www to your server's IP). This is what makes your website load.
• AAAA record — the same idea for IPv6 addresses. Use it when your server has an IPv6 address.
• CNAME record — points one name at another name rather than an IP. Common for subdomains like shop.yourdomain.com pointing to a platform's hostname. A name with a CNAME should not also have other records.
• MX record — tells the world which mail servers accept email for your domain, each with a priority (lower number = tried first). Getting these right is essential for receiving mail.
• TXT record — free-form text used for verification and email authentication. Your SPF policy and DMARC policy both live in TXT records.
• SRV record — advertises the host and port for a specific service (used by some voice, chat and calendar systems).
• NS record — lists the authoritative nameservers for the domain or a subdomain.

A typical, healthy zone

For a standard website with email on the same host, you would usually have: an A record for @ and one for www pointing to your server IP; an MX record pointing to your mail host; and TXT records for SPF and DMARC. That is enough to serve a site and send and receive mail reliably.

Understanding TTL and planned changes

TTL is measured in seconds. A long TTL (say 86400 = one day) means fast, cached lookups but slow changes. Before a planned migration, lower the TTL a day ahead (to 300–600 seconds) so the cutover propagates in minutes rather than hours, then raise it again once everything is stable.

Common mistakes to avoid

• Pointing www with an A record to one IP and @ to another — keep them consistent.
• Adding a CNAME on the root domain (@) — most DNS providers do not allow it; use an A record there.
• Changing nameservers and DNS records at the same time — pick one method (nameservers or individual records) so you always know what is authoritative.
• Forgetting MX records after a move, which silently breaks incoming email.

You manage all of this from your control panel. For step-by-step pointing and transfers, see Domains & DNS, or check a new name with the domain checker.