What is DNS?

DNS (Domain Name System) is the internet's address book. It translates human-readable domain names like google.com into IP addresses like 142.250.185.46 that computers use to communicate.

Without DNS, you'd need to memorize IP addresses for every website you visit. DNS makes the web accessible by turning domain names into machine-readable addresses.

This system works through a hierarchical network of servers that work together to resolve domain names in milliseconds, enabling billions of internet connections every single day.

🔗

Domain → IP Address

example.com ↔ 93.184.216.34

Key DNS Components

Recursive Resolver
Your ISP's DNS server that kicks off the query process
Usually: 8.8.8.8, 1.1.1.1
Root Nameserver
Directs you to the appropriate TLD nameserver
13 servers worldwide
TLD Nameserver
Handles the top-level domain (.com, .org, .net)
.com TLD operated by Verisign
Authoritative Nameserver
Contains the actual DNS records for the domain
Domain registrar or host provider

How DNS Query Works

A DNS query follows a specific path to resolve a domain name. Click on each step to learn more:

1
User Request
→
2
Recursive Resolver
→
3
Root Nameserver
→
4
TLD Nameserver
→
5
Authoritative Server
Step 1: User Request
You type a URL (like example.com) into your browser. Your device doesn't know the IP address, so it sends a DNS query to find it.

Detailed Process

1. User Request: You enter a domain name in your browser. Your computer needs to find the IP address.

2. Recursive Resolver Query: Your device asks a recursive resolver (usually provided by your ISP or a service like Google DNS) to find the address.

3. Root Nameserver: The resolver queries a root nameserver, which says "I don't know this domain, but ask this TLD nameserver."

4. TLD Nameserver: The TLD nameserver (responsible for .com, .org, etc.) says "I don't know this specific domain, but ask the authoritative nameserver."

5. Authoritative Nameserver: Finally, the authoritative nameserver responds with the actual IP address, which gets passed back through the chain.

6. Caching: The resolver caches this result so future queries are faster. Your browser also caches it.

DNS Record Types

Different types of DNS records serve different purposes. Here are the most common ones:

A
Maps domain to IPv4 address
example.com → 93.184.216.34
AAAA
Maps domain to IPv6 address
example.com → 2606:2800:220:1:248:1893:25c8:1946
CNAME
Canonical name - creates alias for domain
www.example.com → example.com
MX
Mail exchange - directs email to mail server
mail.example.com (priority: 10)
TXT
Text records for verification and info
v=spf1 include:_spf.google.com ~all
NS
Nameserver - delegates domain to nameserver
ns1.example.com, ns2.example.com
SOA
Start of authority - zone configuration
Primary NS, admin email, serial number
SRV
Service - defines location of services
_sip._tcp.example.com

Live DNS Lookup Simulator

Try looking up real DNS records for any domain. This uses Google's DNS-over-HTTPS API to fetch live data.

How It Works

This simulator uses the Google Public DNS API (DoH) to perform real DNS queries. It demonstrates how DNS resolution actually works on the internet.

Try these examples: