Internet Diagnostics Utilities

Internet Diagnostics Utilities
CentralOps.net
Free online network utilities, such as ping, nslookup, traceroute.
DNS Tools
Resolve/reverse lookup, whois (domain name), whois (ip owner), check port, ping.
Network-Tools.com
Ping, trace, whois, spam blacklist check, etc.
Online Nettools
Reverse lookup (host), nslookup, whois IP, whois Domain, bandwidth meter, check port, ping host, traceroute to host, port scanner, mail relaying.
Online network tools
Show me my IP address, IP calculator, ping online, traceroute online, IP geolocation, convert IP to domain name, get MX record, DNS dig, Whois, open relay test, speed test, service name -> port TCP/UDP, port TCP/UDP -> service name, online cron generator.
ping.eu
Ping, traceroute, DNS lookup, whois, port check, reverse lookup, proxy checker, mail relaying, bandwidth meter.
T1 Shopper
Whois, ping, port scanner, nslookup, traceroute