When something breaks | a domain won't resolve, mail bounces, a certificate expires | the first job is to see what's actually happening on the wire. These tools query the same DNS, WHOIS, routing and connectivity data that resolvers and mail servers use, so you can diagnose an issue in seconds instead of guessing.
Look up any record type, compare how a name resolves across global public resolvers, confirm DNSSEC validates, check an IP against blocklists, or map the ASN behind an address. Every lookup runs against live infrastructure and nothing is stored. Network engineers, sysadmins and IT leaders reach for them during incident triage, migration cut-overs, deliverability checks and vendor due-diligence.
All Network & DNS tools
16 toolsDNS Lookup
Query A, AAAA, MX, TXT, NS, CNAME, SOA, CAA, SRV records.
Mail Health Report
One domain in, an A–F email deliverability & DNS health score out, SPF, DKIM, DMARC, MX, DNSSEC, blacklist and TLS in one shareable report.
SuperCheck
One box for every lookup: type mx:, spf:, dmarc:, blacklist:, dns:, whois: or a bare domain for the full report.
MX Lookup
Find and test the mail exchangers for a domain.
Reverse DNS (PTR)
Resolve an IP address back to its hostname.
WHOIS Lookup
Registration, registrar and expiry for domains and IPs.
RDAP Lookup
Structured registration data, the modern WHOIS.
DNS Propagation Checker
Compare records across global public resolvers.
DNSSEC Checker
Verify a domain is signed and the chain validates.
Blacklist (DNSBL) Checker
Check an IP or domain against major RBL blocklists.
Subdomain Finder
Enumerate subdomains via certificate transparency.
IP Geolocation
Country, network and ASN for any IP address.
ASN Lookup
Owner and prefixes behind an autonomous system.
What Is My IP Address
Your public IP, headers and network details.
Internet Speed Test
Measure download, upload and latency.