DNS & Domain Tools
DNS records, propagation, and domain health checks
13 tools available — free, instant, no login required
All DNS & Domain Tools
MX Lookup
Check mail exchange records for a domain
DNS Lookup
Query DNS records (A, AAAA, CNAME, TXT, NS, SOA)
AAAA Lookup
Query IPv6 address (AAAA) records
TXT Lookup
Query TXT records for domain verification and policies
CNAME Lookup
Query canonical name (CNAME) alias records
SOA Lookup
Query Start of Authority records for zone information
SRV Lookup
Query service location (SRV) records
DNS Propagation
Check DNS propagation globally across multiple servers
WHOIS Lookup
Domain registration and ownership information
DNSSEC Check
Validate DNSSEC configuration and signatures
Domain Health
Comprehensive domain configuration and health check
DNS Server Finder
Browse and compare public DNS servers — Cloudflare, Google, Quad9 and more
DNS Speed Test
Test and compare DNS resolution speed across Cloudflare, Google, Quad9 and more
Understanding DNS & Domain
The Domain Name System (DNS) is the foundational protocol of the modern internet, defined in RFC 1034 and RFC 1035 by Paul Mockapetris in 1983. It operates as a globally distributed hierarchical database that translates human-readable domain names into machine-readable IP addresses. Every internet communication — from loading a webpage to sending an email — relies on successful DNS resolution. DNS supports multiple record types: A records map domains to IPv4 addresses, AAAA records to IPv6, MX records define mail routing, CNAME records create aliases, TXT records carry arbitrary text data used for SPF/DKIM/DMARC, NS records delegate authority, and SOA records define zone parameters.
DNS security has become critical as attackers exploit it through DNS cache poisoning (Kaminsky attack, CVE-2008-1447), DNS hijacking, DNS amplification DDoS attacks, and domain typosquatting. DNSSEC (RFC 4033–4035) adds cryptographic signatures to DNS responses, creating a chain of trust from the root zone to individual domains. DNS over HTTPS (DoH, RFC 8484) and DNS over TLS (DoT, RFC 7858) encrypt DNS queries to prevent eavesdropping and man-in-the-middle interception. Modern DNS monitoring is essential for detecting propagation delays after TTL changes, identifying misconfigured records causing email delivery failures, and verifying CDN configurations across global PoPs.
Command-Line Usage
Run DNS queries directly from your terminal using these commands:
macOS / Linux: dig example.com A — query A records macOS / Linux: dig example.com MX +short — get mail servers macOS / Linux: dig @8.8.8.8 example.com ANY — query all records via Google DNS Windows CMD: nslookup example.com 8.8.8.8 — lookup via Google DNS Windows PowerShell: Resolve-DnsName -Name example.com -Type MX — PowerShell DNS query Linux: host -t TXT example.com — get TXT records with host command