Back to IP Checker

    DNS Lookup

    Check all public DNS records for any domain including A, AAAA, MX, CNAME, NS, TXT, and more.

    What is DNS?

    DNS (Domain Name System) is like the internet's phone book. It translates human-readable domain names (like example.com) into IP addresses that computers use to identify each other on the network.

    When you type a URL in your browser, DNS servers work behind the scenes to find the correct IP address, allowing your browser to connect to the right web server and load the website.

    DNS Record Types

    A
    Address Record

    Maps a domain name to an IPv4 address. This is the most fundamental DNS record.

    AAAA
    IPv6 Address Record

    Maps a domain name to an IPv6 address for modern internet connectivity.

    MX
    Mail Exchange

    Specifies mail servers responsible for receiving email for the domain.

    CNAME
    Canonical Name

    Creates an alias from one domain name to another (canonical) domain name.

    NS
    Name Server

    Indicates which DNS servers are authoritative for the domain.

    TXT
    Text Record

    Stores text information, commonly used for email verification and security policies.

    Frequently Asked Questions

    In-depth guide

    DNS (the Domain Name System) is the address book of the internet. Every time a browser, app, or server connects to a hostname like example.com, it first asks DNS for the corresponding IP address. A DNS lookup tool queries authoritative nameservers directly and returns the raw records so you can see exactly what the public internet sees — useful for verifying a configuration change, debugging an email problem, or auditing a domain you're about to acquire.

    What each DNS record type does

    An A record maps a hostname to an IPv4 address. AAAA does the same for IPv6. CNAME aliases one hostname to another — useful when you want www.example.com and example.com to resolve to the same place without duplicating records. MX records list the mail servers responsible for receiving email at a domain, ordered by priority. TXT records hold arbitrary text and are used for SPF, DKIM, DMARC, domain ownership verification, and other policy data. NS records identify the authoritative nameservers for the domain. SOA (start of authority) contains the zone's primary nameserver, admin contact, serial number, and refresh timers. CAA records restrict which certificate authorities are allowed to issue TLS certificates for the domain.

    How to read DNS results

    Each record has a TTL (time-to-live) in seconds — the maximum time a resolver may cache the answer before re-querying. Short TTLs (300 seconds, five minutes) make changes propagate quickly but increase query load; long TTLs (24 hours) reduce load but make changes slow to reach end users. When troubleshooting a recent change, always check the TTL of the previous record — that's the upper bound on how long stale data may linger.

    Multiple records of the same type usually mean load balancing or redundancy. Multiple A records on a hostname are returned in rotating order by most resolvers (round-robin DNS). Multiple MX records use the priority number — the lowest priority is tried first, with higher-priority records as fallbacks.

    Common troubleshooting scenarios

    Email not being delivered? Check the MX records first — they must point to a mail server that accepts mail for the domain. Then verify SPF, DKIM, and DMARC in TXT records; missing or misconfigured SPF is the most common cause of legitimate mail landing in spam. A new website not loading? Verify the A or CNAME for both the root domain and www. TLS certificate failing to issue? Check CAA records — if present, they must explicitly authorize your certificate authority (e.g., Let's Encrypt issues from letsencrypt.org). Subdomain takeover risk? Look for CNAME records pointing to deprovisioned services like a deleted Heroku app or unused S3 bucket.

    Frequently asked questions