DNS Lookup

Perform fast DNS lookups to retrieve A, AAAA, CNAME, MX, and NS records of any domain. Ideal for debugging domains, verifying configurations, or conducting audits. Pair this with our Reverse IP Lookup and IP Address Validator to gain complete insight into domain infrastructure.

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Regular Expression - Documentation

What is DNS Lookup?

DNS (Domain Name System) Lookup is the process of translating a human-readable domain (like example.com) into an IP address that computers use to identify each other on the internet.

Think of it as the phonebook of the internet—it helps browsers locate web servers behind the scenes so websites can load.

How DNS Lookup Works

Here’s how a typical DNS resolution process works under the hood:

User Input: A domain like example.com is entered into the browser.
Recursive Resolver: The request is sent to a DNS resolver (often your ISP or configured DNS like Google).
Root Server Contacted: The resolver asks a root server for the .com TLD server.
TLD Server: The .com server tells the resolver where to find example.com’s authoritative DNS.
Authoritative Server: This server gives the final answer—e.g., the IP address linked to the domain.
Response Delivered: The IP is returned to your device, and the browser connects to that IP.

Common DNS Records Explained

A Record: Maps a domain to an IPv4 address
AAAA Record: Maps to an IPv6 address
CNAME: Alias for another domain
MX Record: Mail server for the domain
NS Record: Nameserver in charge of DNS resolution
TXT Record: Text info (e.g., SPF or domain verification)
SOA Record: Start of Authority, contains administrative info

Practical Examples

Example 1: Resolving an IP Address

Input: qodex.ai

Output:

A Record: 34.120.56.73  
NS Record: ns1.gcpdns.net  
MX Record: aspmx.l.google.com

Useful for: Confirming DNS propagation and live server IPs.

Example 2: Diagnosing Email Delivery Issues

You run a DNS lookup on clientdomain.com and find:

MX Record: mail.clientdomain.com  
TXT Record: v=spf1 -all

Here, the SPF record is blocking all senders—explains why emails are bouncing.

Use Cases

Website Debugging: Check if your domain points to the right server.
Email Troubleshooting: Validate MX, SPF, and DKIM DNS entries.
Security Analysis: Detect DNS hijacking or unauthorized nameserver changes.
SEO Monitoring: Ensure CNAMEs and A records are correct post-migration.
IT Audits: Confirm configurations for domains, apps, and services.

Pro Tips

Combine with IP Address Validator to ensure clean, formatted inputs.
For subdomains, always check CNAME records—they might point elsewhere.
If propagation is delayed, test from multiple geographic locations.
DNS TTL (Time to Live) affects how long changes take—always verify TTL settings during migrations.