What DNS records does this tool look up?

This tool queries A, AAAA, MX, NS, TXT, CNAME, and SOA records for any domain using public DNS resolvers (Google DNS and Cloudflare).

How does the SSL certificate checker work?

We establish a TLS connection to port 443 of the domain and extract the peer certificate details including issuer, validity dates, days until expiry, protocol version, and Subject Alternative Names.

What information is included in the WHOIS lookup?

The WHOIS lookup shows the registrar, creation date, expiration date, name servers, domain status, registrant organization, and registrant country when available.

How does redirect chain detection work?

We follow HTTP redirects (3xx responses) from the initial URL, recording each hop with its status code, until we reach the final destination. This reveals redirect chains, protocol upgrades (HTTP to HTTPS), and www normalization.

How is the hosting provider detected?

We combine reverse DNS lookups on the domain's IP addresses with HTTP response header analysis to identify the hosting provider. We check against a database of known providers including AWS, Google Cloud, Azure, Cloudflare, Vercel, and many more.

How is the email provider identified from MX records?

We analyze the domain's MX (Mail Exchange) records and match them against known email provider patterns. This identifies providers like Google Workspace, Microsoft 365, Zoho Mail, ProtonMail, and others.

Free Tools

DNS Lookup Tool

Free DNS lookup with MX record lookup, SSL certificate checker, WHOIS data, reverse DNS, redirect chains, HTTP headers, and hosting provider detection — all in one tool.

What is a DNS lookup?

DNS (Domain Name System) translates human-readable domain names into IP addresses that computers use to communicate. A DNS lookup queries these records to reveal how a domain is configured — including which servers host it (A/AAAA records), where email is routed (MX records), which nameservers are authoritative (NS records), and verification/security policies (TXT records like SPF, DKIM, and DMARC).

Why check SSL certificates?

SSL/TLS certificates encrypt the connection between a browser and a web server. An expired or misconfigured certificate causes browser warnings that drive visitors away and hurt search rankings. Regularly checking your SSL certificate expiry date, issuer, and Subject Alternative Names helps prevent outages and ensures your site remains secure and trusted.

Understanding redirect chains

When you type a URL, the server may redirect you through multiple hops before reaching the final page. Common redirects include HTTP to HTTPS upgrades, www to non-www normalization, and marketing URL shorteners. Long redirect chains add latency and can dilute SEO link equity. This tool traces every hop so you can identify and eliminate unnecessary redirects.

How we detect hosting & email providers

Hosting detection combines reverse DNS lookups on the domain's IP addresses with analysis of HTTP response headers (like the Server header, CDN identifiers, and platform-specific headers). Email provider detection works by analyzing MX records — the DNS entries that specify which mail servers handle email for a domain — and matching them against known provider patterns.

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