DNS Explained

Translate names to numbers

DNS (Domain Name System) maps names such as example.com to IP addresses so people can use memorable names while computers use addresses.

Follow a typical lookup

Your device asks a resolver (often your router or ISP). The resolver may answer from cache or query other DNS servers until it finds the address for the name.

Try a lookup yourself

Use a command-line tool to see what a name resolves to.

# Linux / macOS
nslookup example.com
# or
dig example.com

# Windows
nslookup example.com

Notice what can go wrong

A wrong DNS server, a typo in the name, or a stale cache can make a site "unreachable" even when the network itself is fine. Flushing DNS cache or trying another resolver is a common check.