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Domain Name Lookup

Simple forward and reverse DNS lookups.

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Frequently Asked Questions

What is a DNS query tool?

A DNS query tool sends a direct request to a DNS resolver and shows you the raw records a domain has published — A, AAAA, MX, TXT, CNAME, NS, SOA, and more. Unlike a browser lookup, you choose the record type and resolver, so you can see exactly what a nameserver is returning.

What DNS record types should I know?
  • A — IPv4 address of the domain.
  • AAAA — IPv6 address.
  • CNAME — alias pointing to another hostname.
  • MX — mail server(s) for the domain.
  • TXT — free-text records; used for SPF, DKIM, domain verification.
  • NS — nameservers authoritative for the domain.
  • SOA — start-of-authority; holds the primary NS and serial number.
  • PTR — reverse DNS; maps an IP to a hostname.
What is TTL and why does it matter?

TTL (Time To Live) is the number of seconds resolvers are allowed to cache a DNS record. A TTL of 300 means the record may be cached for up to 5 minutes. Lower TTLs allow faster propagation of changes; higher TTLs reduce DNS query load but mean old records stick around longer after a change.

Why do I get different results from different resolvers?

Results can differ due to caching (each resolver may have cached a different version), geo-DNS (some CDNs return different IPs based on the resolver's location), or propagation delays after a recent DNS change. Use the DNS Propagation tool to query many resolvers simultaneously.

What is the difference between dig, nslookup, host, and drill?

All four query DNS records; they differ in output format and default behaviour. dig is the most verbose and widely used by network engineers. nslookup is the classic Windows/Unix tool. host gives concise output. drill (from ldns) adds DNSSEC chain verification. Use whichever output format you find easiest to read.