Free online network tools, including traceroute, nslookup, dig, whois, ping, and our own Domain Dossier and Email Dossier. Works with IPv6. Some source code included.

• Domain Dossier - Investigate domains and IP addresses. Get registrant information, DNS records, and more—all in one report.
• Domain Check - See if a domain is available for registration.
• Email Dossier - Validate and troubleshoot email addresses.
• Browser Mirror - See what your browser reveals about you.
• Ping - See if a host is reachable.
• Traceroute - Trace the network path from this server to another.
• NsLookup - Look up various domain resource records with this version of the classic NsLookup utility.
• AutoWhois - Get Whois records automatically for domains worldwide.
• TcpQuery - Grab a web page, look up a domain, and more.
• AnalyzePath - Do a simple, graphical traceroute.