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DNS checker

Look up the DNS records published for any domain. Query authoritative or public DNS servers, inspect raw values and TTLs, and see exactly which nameserver answered.

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What the DNS checker looks up

Look up the records that control routing, email delivery, and domain security

Website routing

A, AAAA, and CNAME records show where a hostname points and how requests are routed.

Email routing

MX and TXT records show where email is delivered and how it's authenticated.

Domain control

NS, SOA, CAA, and DNSSEC records show delegation, zone settings, certificate rules, and signing data.

When to check DNS records

After changing DNS:

Confirm that the authoritative DNS server is publishing the updated record and value.

When a website or API fails:

Check address, alias, and nameserver records for missing or unexpected answers.

When email delivery breaks

Inspect MX and TXT records, then run dedicated SPF, DKIM, or DMARC validation where needed.

When DNS servers disagree:

Compare DNS sources to distinguish cached answers from configuration issues.

What DNS records can tell you

Where a domain points

See the IPv4 address, IPv6 address, alias, or service endpoint returned for a hostname.

How email is routed

Identify routing priorities, and the SPF, DKIM, and DMARC records used for email authentication.

Where to look next

Response codes, nameservers, TTLs, and DNSSEC can help identify configuration and caching issues.

How to read DNS results

Name
The exact hostname or owner name that was queried
Type
The kind of DNS record returned
TTL
How long a resolver may cache the record before consulting the source again
Value
The address, hostname, text, key, or policy contained in the record
Priority
The preferred order for records such as MX
Weight
How traffic may be distributed between SRV records with the same priority
Port
The service port published by an SRV record
Query source
The DNS server that returned the answer
Response
The DNS response status, such as NOERROR, NXDOMAIN, SERVFAIL, or REFUSED
Authoritative
Whether the response came from a server responsible for the zone

Common DNS issues

Identify the configuration problems that most commonly affect DNS resolution and email delivery.

Stale or cached DNS records

A DNS resolver may continue returning an older record until the cached entry's TTL expires.

Missing or conflicting records

Missing or conflicting DNS records can break routing, authentication, or service discovery.

Delegation or DNSSEC failures

Incorrect delegation or DNSSEC configuration can prevent resolvers from validating your domain.

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FAQ

What is a DNS checker?

A DNS checker is a tool that looks up the DNS records published for a domain or hostname. It retrieves records such as A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, and DNSSEC, helping you verify DNS configuration, troubleshoot resolution problems, confirm email routing, and check records used for email authentication such as SPF, DKIM, and DMARC.

What is the difference between a DNS lookup and a DNS propagation check?

A DNS lookup retrieves DNS records from a single DNS server, while a DNS propagation check compares the same records across multiple DNS resolvers or locations. Use a DNS lookup to inspect your current DNS configuration, verify record values, or troubleshoot DNS issues. Use a DNS propagation checker after updating DNS records to see whether the changes have propagated across the internet.

What does TTL mean in DNS results?

TTL (Time to Live) is the length of time a DNS resolver caches a DNS record before requesting a fresh copy from the authoritative DNS server. Until the TTL expires, resolvers may continue returning the cached value even if the DNS record has changed. Lower TTL values allow DNS updates to propagate more quickly, while higher TTL values reduce the number of DNS queries.

Why do different DNS servers show different results?

Different DNS servers can return different results because DNS records are cached independently by each resolver. After a DNS record changes, some resolvers may still return the cached value until its TTL expires, while others have already retrieved the updated record from the authoritative nameserver. This is a normal part of DNS propagation.

Can I perform a reverse DNS lookup?

A reverse DNS lookup finds the hostname associated with an IP address by querying the PTR record published under the special in-addr.arpa (IPv4) or ip6.arpa (IPv6) name for that address. This tool looks up records for domain names rather than IP addresses. Note that not all IP addresses have PTR records, so a missing result does not necessarily mean the IP address is unused or misconfigured.

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