Network Tools

DNS Lookup

Query DNS records for any domain. A, AAAA, MX, TXT, NS, CNAME records supported.

What Is DNS and How Does DNS Lookup Work?

DNS (Domain Name System) is the internet's phonebook — it translates human-readable domain names like google.com into numeric IP addresses that computers use to communicate. Every time you visit a website, your browser performs a DNS lookup: it queries a resolver, which traverses the DNS hierarchy to find the authoritative answer for that domain.

Our DNS lookup tool performs live DNS queries directly from our resolver, returning all major record types in real time. This is useful for diagnosing email delivery problems, verifying domain configuration, and checking how quickly DNS changes are propagating.

The DNS Resolution Process

When you type a domain, your OS checks its local cache first. If not found, it queries your configured DNS resolver (often your ISP or a public resolver like 8.8.8.8). The resolver contacts root name servers, then TLD servers (.com, .net), and finally the domain's authoritative name server — returning the IP address or other record back through the chain. This entire process typically takes under 50ms.

DNS Record Types Explained

AMaps a domain name to an IPv4 address (e.g., 93.184.216.34). The most common DNS record type.
AAAAMaps a domain to an IPv6 address. Required for IPv6 connectivity and modern network infrastructure.
MXSpecifies mail server(s) for a domain. Critical for email delivery. Multiple MX records provide redundancy via priority values.
TXTStores text data for SPF, DKIM, DMARC, and domain verification. Essential for email security and anti-spam compliance.
CNAMECreates an alias pointing one domain to another. Used for subdomains, CDN routing, and third-party service integration.
NSIdentifies the authoritative name servers for a domain. These servers hold the official DNS records.
SOAStart of Authority record — defines zone properties including primary nameserver, admin contact, and cache timing (TTL).
PTRPointer record — used for reverse DNS lookup. Maps an IP address back to a hostname. Queried via the in-addr.arpa zone (e.g., 8.8.8.8 → dns.google).

Common DNS Problems and How to Diagnose Them

Email not delivering

Check your MX records — they must point to valid, reachable mail servers. Also verify your TXT record contains a valid SPF entry. Missing or incorrect MX records are the #1 cause of email delivery failure.

Website not loading after DNS change

DNS changes are cached for the duration of the TTL (Time to Live). If your TTL was 86400 (24 hours), visitors' resolvers may serve the old IP for up to 24 hours. Reduce TTL to 300 before making changes to minimize propagation delays.

Domain ownership verification failing

Services like Google Search Console and Microsoft 365 require a specific TXT or CNAME record. Use our lookup tool to confirm the record exists and matches exactly what the service requires.

Need to Look Up a Hostname from an IP? Use Reverse DNS

This tool looks up DNS records for domains. If you have an IP address and want to find its associated hostname (PTR record), that's a reverse DNS lookup — a different query that reads from the in-addr.arpa zone. Common commands: nslookup 8.8.8.8 on Windows, or dig -x 8.8.8.8 on Linux/macOS.

Open Reverse DNS Lookup Tool →

Frequently Asked Questions

What is a DNS lookup?

A DNS lookup is the process of querying the Domain Name System to translate a human-readable domain name (like google.com) into machine-readable information such as IP addresses, mail server records, and other domain configurations. DNS lookups happen automatically every time you visit a website or send an email.

What are the different types of DNS records?

The most common DNS record types are: A records (map domain to IPv4), AAAA records (map to IPv6), MX records (specify mail servers), TXT records (store text data for SPF, DKIM, domain verification), CNAME records (alias one domain to another), NS records (specify authoritative name servers), and SOA records (define zone authority).

Why is DNS propagation slow?

DNS changes can take 24–72 hours to propagate globally because DNS records are cached by resolvers worldwide based on the TTL (Time to Live) value. Lower TTL values mean faster propagation but more DNS queries. To check current propagation status, use our DNS lookup tool to query from our resolver and compare against your registrar settings.

What is an MX record and why does it matter?

An MX (Mail Exchanger) record specifies which mail servers are responsible for receiving email for a domain. If MX records are misconfigured, email delivery will fail. Each MX record has a priority value — lower values indicate higher priority. Most domains have 2–3 MX records for redundancy.

What is a TXT record used for?

TXT records store arbitrary text data associated with a domain. Common uses include: SPF records (define which servers can send email for your domain), DKIM signatures (email authentication), DMARC policies (email fraud prevention), domain ownership verification for Google, Microsoft, and other services.

How do I check if DNS changes have propagated?

Use our DNS lookup tool to query the current DNS records for your domain. Compare the returned IP addresses or values against what you set in your registrar. If the values match your new records, propagation is complete for our resolver. Full global propagation depends on all worldwide resolvers clearing their cache.

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