What Is DNS? A, AAAA, MX, TXT, CNAME Records Explained
What Is DNS?
DNS (Domain Name System) is the internet's address book. When you type a URL like "google.com" into your browser, DNS translates that human-readable name into the IP address (like 142.250.80.46) that computers use to communicate.
How DNS Works
- Your browser asks a DNS resolver (usually your ISP): "What's the IP for google.com?"
- The resolver queries the root nameservers, then TLD nameservers (.com), then Google's authoritative nameservers.
- The authoritative nameserver returns the IP address.
- Your browser connects to that IP.
This entire process typically takes under 50 milliseconds.
Major DNS Record Types
A Record (Address Record)
Maps a domain name to an IPv4 address.
example.com. 300 IN A 93.184.216.34
AAAA Record (IPv6 Address Record)
Maps a domain name to an IPv6 address.
example.com. 300 IN AAAA 2606:2800:220:1:248:1893:25c8:1946
CNAME Record (Canonical Name)
Creates an alias from one domain to another.
www.example.com. 300 IN CNAME example.com.
MX Record (Mail Exchange)
Specifies the mail servers that accept email for a domain, with a priority number.
example.com. 300 IN MX 10 mail.example.com.
TXT Record (Text Record)
Stores arbitrary text data. Used for email authentication (SPF, DKIM, DMARC), domain verification, and more.
example.com. 300 IN TXT "v=spf1 include:_spf.google.com ~all"
NS Record (Name Server)
Specifies the authoritative nameservers for a domain.
example.com. 86400 IN NS ns1.example.com.
SOA Record (Start of Authority)
Contains administrative information about the DNS zone.
Check DNS Records with Our Tool
Use our DNS Analyzer to check all DNS records for any domain, including SPF, DKIM, DMARC, and more.
DNS TTL Explained
TTL (Time to Live) is the number of seconds a DNS record is cached by resolvers. Lower TTL = faster propagation of changes but more DNS queries. Typical values: 300 (5 min), 3600 (1 hour), 86400 (1 day).
Conclusion
Understanding DNS records is essential for anyone managing a website. Use our free DNS Analyzer to inspect any domain's complete DNS setup.