High-Performance Developer Tools
Free, fast, and secure network diagnostic & security tools. No sign-up required, zero rate-limiting hurdles — instant real-time results.
DNS Record Checker
Instantly check A, AAAA, MX, CNAME, NS, TXT, SOA, CAA, SRV records for any domain via DoH.
SMTP Connection Tester
Test SMTP mail server connectivity on ports 25, 587, 465, STARTTLS encryption, and authentication.
RBL Blacklist Checker
Scan your mail server IP or domain against 33 global DNSBL/RBL blacklist zones in parallel for instant reputation.
HTTP Header & Redirect Tracer
Trace complete HTTP/HTTPS redirect chains (301, 302, 307, 308), measure response times, audit security headers, and export cURL.
Domain WHOIS & Expiry Lookup
Query authoritative WHOIS & RDAP registry records. Check domain registrar, creation date, expiry countdown, and status flags.
SSL/TLS Certificate Checker
Inspect SSL/TLS certificates in real-time. Check days until expiration, Root & Intermediate CA chain, SANs, and protocol versions.
SPF, DKIM & DMARC Analyzer
Deep audit email authentication records. Detect SPF lookup limit overages (10 DNS lookups limit), test DKIM keys, and verify DMARC policy.