DNS Lookup

DNS translates human-readable domain names into IP addresses and service configurations. A and AAAA records point a domain to an IPv4 or IPv6 address. CNAME records create aliases that point one domain to another. MX records tell mail servers where to deliver email for your domain. TXT records store arbitrary text and are used for email authentication (SPF, DKIM, DMARC), domain verification (Google Search Console, SSL issuers), and security policies.

When a website is not loading, a DNS lookup is the first diagnostic step. If the A record is missing or pointing to the wrong IP, the browser cannot reach the server at all. If MX records are misconfigured, email to your domain will bounce. After changing DNS records, propagation can take anywhere from a few minutes to 48 hours depending on TTL values and caching by ISPs. This tool queries public DNS-over-HTTPS resolvers, which typically reflect changes faster than your local ISP's DNS cache.