DNS Lookup

DNS (Domain Name System) is the phone book of the internet — every time you type a website address into your browser, DNS translates that human-readable name (like example.com) into the machine-routable IP address the browser actually connects to. But DNS does much more than just IP lookups: it tells mail servers where to deliver email (MX records), verifies that an email actually came from the domain it claims (SPF and DKIM via TXT records), provides redundancy by listing multiple authoritative nameservers (NS records), and allows one domain to be an alias for another (CNAME records, which are how www.example.com usually points to the same server as example.com).\n\nTroubleshooting DNS is one of the most common tasks in web development and IT operations. A new A record you just added 10 minutes ago is not resolving because of propagation delay or a misconfigured TTL. An email campaign is failing because the SPF record has a typo that prevents delivery servers from verifying the sender. A subdomain redirect is not working because the CNAME points to the wrong target. A site is offline but the DNS resolves fine — confirming the problem is at the web server, not at the DNS level. In every one of those scenarios, a quick, reliable DNS lookup tool that queries a real public resolver (not a cached local resolver that might still return stale data) is the first diagnostic tool to reach for.\n\nThis tool performs real-time DNS queries from our server using the operating system\u0027s DNS resolver (PHP\u0027s dns_get_record function, which calls the system\u0027s configured resolver — typically your hosting provider\u0027s DNS or a public resolver like 8.8.8.8). This means you get the same DNS answers that any external system trying to reach that domain would get — not cached results from your local machine or browser\u0027s DNS cache. No results are cached between requests on our side, so repeated queries always hit the live DNS system.\n\nThe seven supported record types cover the vast majority of DNS troubleshooting needs. A records return IPv4 addresses. AAAA records return IPv6 addresses. MX records return the domain\u0027s mail exchange servers with their priority values (lower = higher priority). NS records return the authoritative nameservers for the domain. TXT records return arbitrary text strings — used for SPF (sender policy framework), DKIM (domain keys identified mail), DMARC, domain verification tokens for services like Google Workspace, and more. CNAME records return canonical names — the real hostname this record points to. SOA records return the start of authority — the primary nameserver, the admin\u0027s email, the serial number (used for zone transfers), and timing values.\n\nA note on propagation: when you add or change a DNS record, the change is not instant worldwide. Each record has a TTL (time to live) in seconds that tells other DNS servers how long to cache it. A record with a 1-hour TTL can take up to an hour to propagate after a change because intermediate resolvers will return the old cached value until the TTL expires. If you just updated a record and this tool still shows the old value, check the TTL — if it is high (e.g., 86400 seconds = 24 hours), the change may simply need time to propagate. Reducing the TTL before making a planned DNS change is a standard best practice.