DNS Lookup Commands: How to Use dig, nslookup and host

Applies to: dig and host (bind9-dnsutils or bind-utils) on Linux and macOS, nslookup on Windows, Linux and macOS

DNS lookup commands show which IP address, mail server or text record a domain returns, straight from DNS. They are the quickest way to check a DNS change or find out where a domain points. We ran every example below.

dig (Linux, macOS)

dig example.com                    # full answer with details
dig +short example.com A           # just the IPv4 address
dig +short example.com AAAA        # IPv6
dig +short example.com MX          # mail servers, with priority
dig +short example.com TXT         # SPF, verification records
dig +short example.com NS          # the domain's nameservers
dig +short example.com A @1.1.1.1  # ask a specific DNS server
dig +trace example.com             # follow the lookup from the root servers down

Install it with sudo apt install bind9-dnsutils (Ubuntu, Debian) or sudo dnf install bind-utils (AlmaLinux, Rocky Linux).

nslookup (Windows, Linux, macOS)

nslookup example.com
nslookup -type=MX example.com
nslookup -type=NS example.com
nslookup example.com 8.8.8.8       # ask Google's public DNS

host (Linux, macOS)

host example.com
host -t MX example.com

More examples: useful host command examples.

Common checks

• Has my DNS change reached the internet? Compare your provider’s nameserver with public resolvers: dig +short example.com A @1.1.1.1 and @8.8.8.8. If they show the new address, your own computer may just need its DNS cache flushed.
• Which nameservers does my domain use? dig +short example.com NS.
• Why does my site show a Cloudflare IP? Proxied records return Cloudflare’s addresses, not your server’s.
• Reverse lookup (IP to name): dig +short -x 203.0.113.10.

Record types explained: wildcard records and SRV records.