DNS Records Checker
Check a website's DNS records
DNS Records Checker: how to check DNS records of a domain online
The DNS records, or DNS entries, are essential for the operation of a website, an email service, or an application accessible on the Internet. They allow, among other things, associating a domain name with an IP address, configuring mail servers, verifying domain ownership, or declaring the servers responsible for a domain.
When a website stops working, a subdomain does not respond, an email fails to reach its destination, or an external service asks to add a DNS record, knowing how to view a domain's DNS becomes particularly useful.
With DNS Records by PleaseTools, you can easily view the DNS records published for a domain or a web address, directly from your browser.
What is a DNS record?
The DNS (Domain Name System) is the system that matches domain names used by Internet users with the information computers need to communicate on the Internet.
For example, when a user types:
example.com
their computer must determine which server to send the request to.
This information is notably provided by DNS records.
A DNS record is therefore an entry associated with a domain name that contains a specific piece of information.
Depending on its type, a DNS record can indicate:
- the IPv4 address of a server;
- the IPv6 address of a server;
- the mail server responsible;
- another domain name;
- the authoritative DNS servers;
- a verification information;
- authorized certification authorities;
- or the configuration of certain services.
The main types you will encounter are A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, SRV and PTR.
Why check a domain's DNS records?
Viewing a domain's DNS can be useful in many situations.
Check which server a domain points to
An A record allows you to determine the IPv4 address associated with a domain.
For example:
example.com → 203.0.113.10
This can be especially useful after a server migration or a hosting change.
Check a subdomain
Subdomains also use DNS records.
For example:
www.example.com
api.example.com
mail.example.com
app.example.com
A DNS issue can prevent a subdomain from working while the main domain works perfectly.
Check email configuration
MX records allow you to determine which servers should receive emails sent to a domain.
A bad DNS configuration can thus cause problems receiving or sending email.
Check SPF, DKIM, or DMARC configuration
TXT records are frequently used for configuring and verifying Internet services.
They can notably contain information related to:
- SPF;
- DKIM;
- DMARC;
- domain ownership verification;
- certain Google, Microsoft, or other platform services.
Check DNS servers
NS records allow you to know the authoritative DNS servers for a domain.
This is particularly interesting when a domain has just been transferred or its DNS has been changed.
Diagnose a DNS problem
When a site is inaccessible or a DNS change seems not to work, viewing the published records allows you to verify what is actually visible on the Internet.
Main DNS record types
Understanding the different DNS record types helps better interpret the results of a DNS query.
A Record: IPv4 address
The A record associates a hostname with an IPv4 address.
Example:
example.com A 203.0.113.10
This means that the domain example.com has an IPv4 address of 203.0.113.10.
It is one of the most important records for a website.
What is an A record used for?
- point a domain to a web server;
- set up hosting;
- enable a subdomain;
- associate a name with a public IPv4 address.
AAAA Record: IPv6 address
The AAAA record plays a similar role to the A record, but for IPv6 addresses.
Example:
example.com AAAA 2001:db8::10
A domain can therefore simultaneously have:
A → IPv4 address
AAAA → IPv6 address
The presence of an AAAA record allows IPv6‑compatible clients to access the server directly via IPv6.
CNAME Record: alias to another domain
A CNAME record allows a name to point to another hostname.
Example:
www.example.com CNAME example.com
This means that www.example.com is an alias of example.com.
CNAMEs are widely used for:
- subdomains;
- SaaS services;
- hosting platforms;
- CDNs;
- certain cloud services.
Unlike an A record, a CNAME points to another name, not directly to an IP address.
MX Record: email configuration
The MX (Mail Exchange) record indicates which servers should receive emails destined for a domain.
Example:
example.com MX 10 mail.example.com
The number represents the server's priority.
With multiple servers:
example.com MX 10 mail.example.com
example.com MX 20 backup.example.com
The server with the highest priority according to the lowest preference value is usually tried first.
MX records are therefore essential for diagnosing mail issues.
TXT Record: textual information
A TXT record allows publishing textual information associated with a domain.
It is today used for many functions.
For example, a domain can publish an SPF record:
v=spf1 include:example.com ~all
TXT records are notably used for:
- SPF;
- DKIM;
- DMARC;
- domain ownership verification;
- certain service configurations;
- validation of external platforms.
If a service asks you to add a TXT value to your domain, you will generally need to make this change from your DNS provider's interface.
NS Record: authoritative DNS servers
NS (Name Server) records indicate the name servers responsible for the DNS zone.
Example:
example.com NS ns1.example-dns.com
example.com NS ns2.example-dns.com
They allow, among other things, identifying the provider or DNS infrastructure managing the domain's records.
NS records are particularly important during:
- a registrar change;
- a DNS provider change;
- a domain migration;
- a general DNS resolution issue.
SOA Record: primary zone information
The SOA (Start of Authority) record contains important information about the DNS zone.
It can notably contain:
- primary DNS server;
- zone administrator's email address;
- zone serial number;
- refresh interval;
- retry interval;
- expiry time;
- negative TTL.
The SOA is mainly interesting for system administrators and people who need to diagnose or manage a DNS zone.
CAA Record: SSL/TLS certificates
CAA (Certification Authority Authorization) records indicate which certification authorities are authorized to issue certificates for a domain.
They can be used to strengthen control over SSL/TLS certificate issuance.
For example, a domain can declare an authorized certification authority to issue its certificates.
This can be particularly interesting for administrators and DevOps teams who want better control over their TLS infrastructure.
SRV Record: service discovery
SRV records indicate where a particular service is located.
They can contain information such as:
- hostname;
- port;
- priority;
- server weight.
They are notably used by certain protocols and network services.
PTR Record: reverse DNS resolution
A PTR record is used for reverse DNS resolution.
whereas:
domain name → IP address
reverse DNS allows to do:
IP address → hostname
PTR records are particularly important in certain network environments and for mail server configuration.
Summary table of DNS records
| Type | Primary function | Example use |
|---|---|---|
| A | Name → IPv4 | Web server |
| AAAA | Name → IPv6 | IPv6 server |
| CNAME | Name → another name | Alias, subdomain |
| MX | Email handling | Mail server |
| TXT | Textual information | SPF, DKIM, DMARC, verification |
| NS | Authoritative DNS servers | Zone management |
| SOA | Zone information | DNS administration |
| CAA | Authorized certification authorities | SSL/TLS |
| SRV | Service location | Network services |
| PTR | IP → name | Reverse DNS |
How to check a domain's DNS online?
You don’t necessarily need to install software or use the dig command to view a domain’s DNS information.
With DNS Records by PleaseTools, the lookup can be performed directly from your browser.
Step 1: enter the domain
Enter the site address or domain you want to analyze.
For example:
example.com
You can also use a full address such as:
https://example.com
Step 2: start the search
Click Validate.
The tool queries the DNS information available for the domain and displays the corresponding results.
Step 3: analyze the records
Examine especially the records:
- A;
- AAAA;
- CNAME;
- MX;
- TXT;
- NS;
- and other available information.
You can thus quickly identify the published DNS configuration for the domain.
Example: check a website's server
Suppose you want to know which IP address the following points to:
example.com
If you get:
A 203.0.113.10
it indicates that the domain has an A record corresponding to this IPv4 address.
If you also get:
AAAA 2001:db8::10
the domain also has a published IPv6 address.
Example: check a domain's emails
To understand where a domain's emails are sent, look up its MX records.
For example:
example.com MX 10 mail.example.com
You can then verify that the domain indeed has a mail server configured.
If no MX record is present, this can be an important element to examine when a mail reception problem is encountered.
Check SPF, DKIM and DMARC with TXT records
TXT records are particularly interesting for email administration.
SPF
SPF allows publishing the servers authorized to send emails for a domain.
Example:
v=spf1 include:mail.example.com ~all
DKIM
DKIM also uses DNS to publish a public key allowing mail servers to verify message signatures.
DMARC
DMARC allows publishing a policy regarding emails that fail authentication checks.
A correct DNS configuration of SPF, DKIM and DMARC helps improve email authentication reliability.
DNS and propagation: why changes are not always immediate?
A DNS change is not necessarily visible everywhere on the Internet immediately.
The main reason is DNS caching.
DNS resolvers keep responses for a set duration, notably defined by the TTL (Time To Live).
Consequently, after a record change, some users may temporarily get the old value while others already see the new one.
Therefore, it's better to check DNS after a change rather than simply assuming the change is already visible everywhere.
The term “DNS propagation” is commonly used to describe this phenomenon, but technically it is mainly about expiration and renewal of cached data by various resolvers.
DNS Records vs Whois: what's the difference?
DNS and Whois provide different information.
DNS Records
DNS records allow you to know:
- the IP address of a server;
- mail servers;
- DNS servers;
- aliases;
- TXT information;
- certain service configurations.
Whois
Whois rather provides information about the domain and its registration, based on publicly available data and registry policies.
The two tools are therefore complementary.
DNS Records for developers
Developers regularly consult DNS when deploying applications.
For example, when deploying a Laravel application, an API or a web service, it may be necessary to configure:
example.com
api.example.com
www.example.com
with different DNS records.
DNS is also important when using:
- VPS servers;
- shared hosting;
- Cloudflare;
- CDN;
- cloud platforms;
- SaaS services;
- APIs;
- SSL certificates;
- email services.
A simple A or CNAME record problem can prevent an application from being reachable via its domain name.
DNS Records for system administrators and DevOps
For a system administrator, checking DNS is one of the first steps when a service seems inaccessible.
A simple diagnostic method consists of checking:
- authoritative DNS servers;
- A and AAAA records;
- CNAME;
- MX for mail;
- TXT for configurations and verifications;
- TTL;
- possible CAA or SRV records.
This allows quickly distinguishing a DNS problem from an issue originating from the server, network, or application.
Using dig to check DNS
Developers and administrators can also use the dig command from a terminal.
To look up an A record:
dig example.com A
To look up MX records:
dig example.com MX
To look up TXT records:
dig example.com TXT
To look up NS records:
dig example.com NS
Using dig is very handy for technical diagnosis, but an online tool can be faster when you simply want to view DNS information without using the terminal.
Why use an online DNS lookup?
- no installation;
- accessible from a browser;
- works on computer or mobile;
- useful for a quick check;
- developer-friendly;
- handy for system administrators;
- allows quick verification of a remote domain.
DNS Records by PleaseTools
DNS Records by PleaseTools allows you to search for DNS records associated with a website or domain directly from your browser.
It can be used to:
- verify a domain’s DNS configuration;
- look up an IP address;
- check MX records;
- examine TXT records;
- identify DNS servers;
- check CNAMEs;
- diagnose certain configuration issues;
- perform a quick check before or after a DNS change.
To get started, simply enter the domain or site address to analyze, then start the lookup.
Frequently asked questions about DNS records
What is a DNS record?
A DNS record is an entry in a domain's DNS zone that contains information used for DNS resolution or service configuration.
What is the difference between A and AAAA?
An A record maps a name to an IPv4 address while an AAAA record maps a name to an IPv6 address.
What is a CNAME used for?
A CNAME creates an alias that points to another hostname.
What are MX records for?
MX records indicate the servers that receive emails destined for a domain.
What are TXT records for?
TXT records can contain various textual information. They are notably used for SPF, DKIM, DMARC and domain ownership verification.
How to find a domain’s IP address?
You can look up its A record to find its IPv4 address and its AAAA record to find its IPv6 address.
Why doesn’t my DNS show a change immediately?
DNS responses can be cached for the duration indicated by the TTL. A change may therefore take time before it is visible to all resolvers.
Is it possible to check a domain’s DNS without installing software?
Yes. An online DNS lookup service allows you to view DNS information directly from a browser.
Conclusion
DNS records are a fundamental part of Internet infrastructure. They allow, among other things, linking a domain to a server, configuring emails, managing subdomains, and verifying various services associated with a domain.
Understanding the main records A, AAAA, CNAME, MX, TXT and NS already enables you to solve a large portion of common DNS problems.
For developers, system administrators and website owners, knowing how to view this information is therefore a particularly useful skill.
👉 Use DNS Records by PleaseTools to quickly check a domain’s DNS records online.