DNS Lookup Tool

What is DNS?

The Domain Name System (DNS) is the internet's phonebook. It translates human-readable domain names like example.com into numerical IP addresses like 93.184.216.34 that computers use to communicate. Without DNS, you would need to memorize IP addresses for every website you visit.

DNS is a hierarchical, distributed database. When you type a URL into your browser, your request passes through multiple DNS servers — from your local resolver to root servers, TLD servers, and finally the authoritative name server for the domain — until the correct IP address is found. This entire process typically takes just milliseconds.

Understanding DNS Record Types

A records are the most common DNS record type. They map a domain name directly to an IPv4 address. A domain can have multiple A records for load balancing, pointing to different servers. AAAA records serve the same purpose but for IPv6 addresses, the newer 128-bit addressing format designed to replace the limited IPv4 address space.

MX records (Mail Exchange) direct email to the correct mail server. Each MX record includes a priority value — lower numbers are tried first. This allows fallback mail servers: if the primary server (priority 10) is unavailable, email is routed to the backup (priority 20).

TXT records store arbitrary text and are heavily used for email security. SPF records (starting with v=spf1) define which IP addresses are authorized to send email for a domain. DKIM records contain public keys for verifying email signatures. DMARC records (on the _dmarc subdomain) set policies for handling authentication failures.

CNAME records (Canonical Name) create aliases, pointing one domain name to another. For example, www.example.com might CNAME to example.com. NS records identify the authoritative name servers for a zone. SOA records (Start of Authority) contain zone metadata including the primary name server, administrator email, serial number, and timing parameters for zone transfers. CAA records specify which Certificate Authorities are permitted to issue SSL/TLS certificates for a domain.

Frequently Asked Questions

What is a DNS lookup?

A DNS lookup queries the Domain Name System to find records associated with a domain name. The most common lookup resolves a domain to its IP address (A record), but you can also query for mail servers (MX), text records (TXT), name servers (NS), and more. This tool uses Google's public DNS-over-HTTPS API to perform lookups.

What is an A record?

An A record (Address record) maps a domain name to an IPv4 address. It is the most fundamental DNS record type. When you visit a website, your browser performs an A record lookup to find the server's IP address. A domain can have multiple A records pointing to different IPs for redundancy and load balancing.

What is an MX record?

An MX record (Mail Exchange) tells sending mail servers where to deliver email for a domain. Each MX record has a priority number — lower values are preferred. For example, a domain might have an MX record with priority 10 pointing to its primary mail server and priority 20 pointing to a backup server.

What is a TXT record used for?

TXT records store text data in DNS and are used for email authentication (SPF, DKIM, DMARC), domain ownership verification, and security policies. SPF records specify which servers can send email for your domain. DKIM records hold cryptographic public keys. DMARC records define how to handle emails that fail authentication checks.

How long does DNS propagation take?

DNS propagation typically takes 15 minutes to 48 hours, with most changes visible within 1-4 hours. The speed depends on the TTL (Time to Live) of the old records — resolvers cache records until the TTL expires. To speed up propagation, lower your TTL well before making changes, then raise it again afterward.