DomainDig is a fast, no-frills domain inspection tool for developers, sysadmins, and anyone who manages or troubleshoots servers and infrastructure. Enter any domain and run a full diagnostic in seconds: DNS: query A, AAAA, MX, NS, TXT, and CNAME records including wildcard entries, with TTL values and reverse DNS (PTR) lookup for the resolved IP. SSL/TLS: inspect the full certificate chain: common name, SANs, issuer, validity dates, and days until expiry with automatic color-coded warnings. Email Security: parse SPF, DMARC, and DKIM records with pass/fail indicators so you can verify email deliverability at a glance. HTTP Headers: fire a HEAD request and review all response headers, with security-relevant headers (HSTS, CSP, X-Frame-Options, and more) highlighted automatically. Redirect Chain: trace every HTTP redirect hop from initial request to final destination, with status codes at each step. Reachability: measure TCP latency on ports 80 and 443, and scan common ports (FTP, SSH, SMTP, MySQL, PostgreSQL, and more) to see what's open. IP Geolocation: look up the hosting org, city, region, and country for the resolved IP, with a live map view. All results load in parallel and independently. Save domains for quick re-runs, browse full lookup history with cached results, and export everything as a plain text file. No accounts. No ads. No tracking.