Expansion collection
IP, DNS, Network & Developer Lookup Sites
DNS, email authentication, TLS, headers, uptime, redirects, and website-owner diagnostics.
28 planned tools 25 live now
Tools
Network lookups
DNS propagation checker Developer Tools — Advanced Live SPF record checker Developer Tools — Advanced Live DKIM record checker Developer Tools — Advanced Live DMARC policy checker Developer Tools — Advanced Live SSL expiry monitor Check TLS certificate issuer expiry SAN domains and validity for a website. Live Redirect chain checker Trace every HTTP redirect hop final URL status code and protocol change for a website. Live Website uptime checker Check whether a website is up from Instant's server with DNS status redirects response code and timing. Live HTTP header checker Fetch response headers and highlight cache security CORS content type and server details. Live Robots.txt tester Test whether a URL path is allowed or blocked for Googlebot Bingbot or another crawler. Live Open Graph meta debugger Fetch title description canonical Open Graph and Twitter card tags with an image preview URL. Live Broken link checker Crawl a page and report broken internal external and redirected links with status codes. Live Email blacklist checker Check a domain or IP against common DNSBL blocklists for mail delivery risk. Live Domain expiry checker Look up RDAP registration data registrar status and expiry date for a domain. Live SSL mixed content checker Scan an HTTPS page for insecure HTTP images scripts styles iframes and other assets. Live Page size / asset weight checker Estimate page HTML size linked asset counts and rough script style image weight from a URL. Live XML sitemap validator Validate sitemap XML structure limits URL fields dates changefreq and priority values. Live CDN provider detector Detect common CDN providers from CNAME and nameserver DNS signatures. Live Open port checker Queued from the expansion plan Search TLS cipher suite checker Queued from the expansion plan Search HSTS preload checker Developer Tools — Advanced Live Content-Security-Policy header generator Developer Tools — Advanced Live DNS SOA record lookup Look up and explain SOA record fields over Cloudflare DNS-over-HTTPS. Live DNS CAA record lookup Look up CAA records and explain authorized certificate issuers. Live DNS TXT record lookup Look up TXT records and classify SPF DKIM DMARC and verification records. Live DNSSEC checker Check DNSKEY DS records and resolver AD validation status using DNS-over-HTTPS. Live IPv6 readiness checker Check root www and mail host AAAA records for IPv6 readiness. Live Email DNS health checker Check MX SPF and DMARC DNS records with practical email-health grading. Live Favicon existence/format checker Queued from the expansion plan Search