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A Record Lookup

The A Record Lookup tool is an online tool that lets you query DNS servers to check A records and get instant results.

IPv4, Address, or A record lookups are used to determine the A records associated with a domain.

Looking for easier to understand results? Use the Global DNS Checker tool.

DNS A Record

A records, known as Address records are used to store IP address information for a domain name.

A records can only store IPv4 IP addresses (e.g. 192.168.2.1). In order to store IPv6 addresses, an AAAA record must be used.

Most websites only need to have a single A record for a given identifier, however it is possible to provide multiple A records.

There are tools available which can convert IPv6 to IPv4, or convert IPv4 to IPv6.

Example A record

An example A record may look like the following:

Record Type Value TTL
www A 192.168.2.1 3600

www represents identifier of the record. To set the value for the root of the domain you must use @.

A is the record type.

192.168.2.1 is the value of the record. This must be an IPv4 address.

3600 is the TTL (time to live) of the record in seconds, this example represents 1 hour. This means that when a record has had updates made to it, then it will take 1 hour to update.

Multiple A records

When multiple A records are associated with the same domain record, one is used at random - this can be useful for larger websites or services as a technique to load balance traffic across multiple servers where a single server or network device cannot handle the traffic alone.

Record Type Value TTL
www A 192.168.2.1 3600
www A 192.168.2.2 3600

When to use A records and why are they useful?

A records are used to point DNS records to IP addresses. This can be useful for a variety of reasons but in some circumstances may not be the right choice.

If you have already defined an A record you may want to consider using a CNAME record instead - this will allow you to point one DNS record to another DNS record, this means you only need to set the IP address with an A record once which can help make maintaining changes easier.

If you need to assign an IPv6 address to a DNS record, then you must use an AAAA record instead.

Some reasons why you may want to use an A record include:

Easier to remember - A records let you point names to IP addresses - names are much easier to remember than IP addresses. Most people would agree that remembering example.com over 192.168.2.1 is much easier, and often is immediately recognised as a website which is really helpful for branding.

Less prone to error - Using IP addresses can be confusing, and not always immediately obvious if there's an error. A records allow you to assign a name to an address, which is often a word or brand name which can be easily checked for spelling errors.

Easier management - Server administrators will often have many servers that they need to manage, giving servers meaningful names by using A records can often give insight into a server's purpose and location. For example, imagine the A record pre-production-001.us-west-1.example.com. This technique could be used to help identify any number of useful details about a server.

Easy to change servers - By having an A record point to an IP address, connecting client machines can continue to connect to a single endpoint without any configuration changes. The changes can be made to the IP address of the A record, which will be updated around the world as DNS propagates.

Load balancing - By assigning multiple IP addresses to an A record, clients will pick one at random to use when connecting to the server specified. This can help spread the load against multiple servers.

How do you perform a DNS lookup to check A records?

Checking A records is easy, but can be done in a variety of ways. The easiest way to find the A records for a domain is to simply use the A record lookup tool on this page.

If you need additional technical details not provided by online tools, or need to test records from your own local network then you may choose to use some of the command-line tools available on your local device. These tools let you do a DNS lookup locally and are generally aimed at more advanced users and can be difficult to understand. The tools available will also depend on your operating system.

Checking A records online

Using the online A record lookup tool to check DNS records is easy. Enter the domain name you wish to check into the search box, optionally choose the DNS server that you would like to check against and press search. The tool will instantly do a DNS lookup and search for A records on the entered domain and return results in an easy-to-read format with having highlighted the results.

Online tools for checking DNS records can often be helpful, but can at times be quite limited for advanced situations and do not represent what you are seeing on your local device or network. It can be a good idea to not only check A records with online tools, but also check them locally to compare results.

Checking A records on Windows

Windows provides the command-line utility called nslookup. This tool is available to use on all versions of Windows including 7, 8, 10, 11 and Windows Server. The tool lets you lookup DNS records on your local device, but is more complicated to use than online tools like the one found on this page.

Using the nslookup command

Using the locally configured resolver:

nslookup
> set q=a
> www.example.com

Using a specific resolver:

nslookup
> set q=a
> server 1.1.1.1
> www.example.com

Checking A records on Linux and Mac

You can perform a DNS lookup request to check DNS records, including A records, on both Mac and Linux operating systems using either the host tool, or the more advanced dig tool. This includes the latest MacOS and older Mac OS X as well as most available Linux distributions like CentOS, Debian, Red Hat & Ubuntu.

Using the host command

Using the locally configured resolver:

host -t a www.example.com

Using a specific resolver:

host -t a www.example.com 1.1.1.1

Using the dig command

Using the locally configured resolver:

dig a www.example.com

Using a specific resolver:

dig a www.example.com @1.1.1.1