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A Record Lookup

Find the IP address of a domain. You see the IPv4 and IPv6 addresses, the CNAME chain that leads to them, and the reverse DNS name of every address.

Try:

Your browser sends the query straight to the resolver you choose over HTTPS (DNS over HTTPS). It does not go through our server.

What an A record is

An A record connects a name to an IPv4 address, such as 93.184.216.34. Its IPv6 twin is the AAAA record. When you type a web address, your browser asks DNS for these records to find the server. This lookup shows both, so you know where a name points.

What you get

  • IPv4 and IPv6 addresses with their TTL. Choose to look up one of them or both.
  • The CNAME chain. Many names are aliases. For www.example.com the chain may go through several names before it reaches an address, and the lookup lists every step.
  • Reverse DNS. For each address, the tool asks for the PTR record, which often shows the name of the hosting company or the CDN.
  • Address type. Each address is marked as public, private, loopback, link-local or shared address space. A public name that points to a private address, such as 192.168.1.10, is usually a mistake.

Several addresses for one name

A name can have many A records. This is called round robin: resolvers return them in changing order, and clients spread the load between them. Large sites also use many addresses for redundancy. The order in the result is not important.

A record or CNAME?

  • Use an A record when you know the IP address of the server.
  • Use a CNAME when a name should follow another name, such as www pointing to your host or a CDN. A CNAME cannot sit next to other records on the same name, and it cannot be used at the root of a domain (the apex), where the NS and SOA records live. Many DNS providers offer an ALIAS or flattened CNAME for that case.

Common reasons for a wrong result

  • The A record points to an old server after a move. Check the TTL and wait for it to pass.
  • The record exists for the root domain but not for www, or the other way round.
  • An AAAA record points to an IPv6 address where the server does not listen, so some visitors see errors.
  • A CDN or proxy hides the real address, and you see the address of the proxy.

For all record types at once, use the DNS lookup. To see whether two resolvers agree after a change, use the DNS record checker. Read about address blocks in the CIDR guide, and work with ranges in the CIDR to IP range tool. The DNS records guide explains the types.

Frequently asked questions

How do I find the IP address of a domain?

Enter the domain and press Lookup. The A records are its IPv4 addresses and the AAAA records are its IPv6 addresses.

Why does a domain have several IP addresses?

For load balancing and redundancy. Resolvers return the addresses in changing order, and clients use any of them.

What is the reverse DNS name?

It is the PTR record of an IP address, a name that the owner of the address has set. It often shows the host or the network.

Can I use a CNAME at the root of my domain?

No. The root needs other records, and a CNAME cannot share a name with them. Use an A record, or an ALIAS or flattened CNAME if your DNS provider has one.