DNS Lookup

Understand how DNS records work and explore the different record types that keep every domain on the internet running.

What are DNS records?

The Domain Name System (DNS) is the backbone of the internet. DNS records determine how each domain is understood by computers — translating human-readable domain names into the IP addresses that servers actually use. When you enter a domain in a browser, a DNS resolver checks its cache first, then queries authoritative name servers until the domain resolves to an IP address.

Forward DNS lookup

Resolves a domain name into its corresponding IP address — the most common type of DNS query performed by browsers and applications.

Reverse DNS lookup

Does the opposite — takes an IP address and returns its associated domain name. Commonly used for email validation and identifying server owners.

Types of DNS records

MX record

Any domain that sends or receives email must have an MX record configured. It tells other mail servers where to deliver messages for your domain.

CNAME record

The canonical name record acts as an alias, pointing one hostname to another. It's commonly used to map subdomains like www to the root domain.

A record

The A record maps a domain name to its IPv4 address, making it possible to reach a server using a human-readable name instead of a raw IP.

AAAA record

The quad-A record works like an A record but maps a domain to an IPv6 address. It's essential for domains that support the modern IPv6 protocol.

NS record

Name server records identify which DNS servers are authoritative for a domain. Every domain must list at least one NS record in its zone.

SRV record

Service records define the hostname and port for specific services on a domain, such as VoIP, instant messaging, or other protocol-level services.

SOA record

The start of authority record contains authoritative information about a DNS zone, including the primary name server and zone refresh intervals.

TXT record

Text records hold arbitrary data about a domain. They are widely used for ownership verification and email authentication via SPF, DKIM, and DMARC.

Reverse IP record

A PTR record performs the reverse of an A record lookup — it resolves an IP address back to its associated domain name, useful for email validation.

Frequently Asked Questions

Do I need DNS records?

DNS records connect domain names to the servers that host your website, handle your email, and run your services. Without them, visitors would have to memorise raw IP addresses — which is not realistic at scale. Every functioning domain on the internet depends on at least a basic set of DNS records to operate.

Can I delete DNS records?

Records can be removed through your domain registrar or DNS provider, but deletions are usually permanent and cannot be reversed. Removing the wrong record can take your website, email, or other services offline until the entry is recreated and finishes propagating. Always double-check before deleting anything from your zone file.

What is a DNS cache?

A DNS cache is a short-term store of recent lookup results kept by your browser, operating system, and ISP. It speeds up browsing by skipping repeated queries for the same domain. If a cache holds stale or incorrect data, flushing it forces a fresh lookup and often resolves unexpected connectivity problems.

How long do DNS changes take to propagate?

Propagation speed depends on the TTL value that was set on the record before the change was made. A TTL of 3600 seconds allows resolvers to cache the old value for up to an hour. In practice most users see updates within minutes to a few hours, but complete global propagation can take up to 48 hours. Lowering the TTL ahead of a planned change is the best way to reduce that window.

What is the difference between authoritative and recursive DNS?

An authoritative DNS server stores the actual records for a domain and gives definitive answers about it. A recursive resolver — used by your ISP or a public service like Google's 8.8.8.8 — acts on your behalf, querying authoritative servers and caching results to speed up future requests. When you look up a domain, your device contacts a recursive resolver, which then works through the DNS hierarchy to find the authoritative answer.