LAB / EXPERIMENT
DNS Resolver
Type any domain name and watch the recursive DNS lookup process unfold step by step — from your device's cache through root servers, TLD servers, and authoritative nameservers to the final IP address.
Related reading: What Is a Packet?
Enter a domain name and press "Resolve" to watch the DNS resolution process step by step — from your device through root servers to the authoritative nameserver.
What This Shows
Every time you type a URL, your browser needs to translate the human-readable domain name into a machine-readable IP address. This process is called DNS resolution, and it happens before any data is exchanged.
The DNS system is hierarchical — like a tree. The root servers (there are 13 logical root server clusters) know which servers handle each top-level domain (.com, .fyi, .org). The TLD servers know which nameservers are authoritative for each registered domain. The authoritative nameserver holds the actual IP address.
In practice, most of this chain is cached. Your ISP's resolver probably already knows the IP for popular domains. The TTL (time-to-live) on each DNS record determines how long it can be cached — when it expires, the resolver must repeat the lookup.
Notice that every server in the chain sees which domain you're looking up. This is why DNS-over-HTTPS (DoH) and DNS-over-TLS (DoT) were created — to encrypt DNS queries so intermediaries can't see what domains you're resolving.