DNSChecker.org - Check DNS Propagation worldwide. DNS Checker provides name server propagation check instantly. Changed nameservers so do a DNS lookup and check if DNS and nameservers have propagated.
MxToolBox - All of your MX record, DNS, blacklist and SMTP diagnostics in one integrated tool.
WhatsMyDNS.ME - WhatsmyDNS provides free DNS Resolution Check for checking if your DNS Records are updated in the various locations worldwide.
intoDNS - IntoDNS checks the health and configuration and provides DNS report and mail servers report.
Whats My DNS - Instantly check your domain names current IP address and DNS record information against multiple name servers located in different parts of the world.
SolveDNS - SolveDNS works to check your name servers, a records, and mail servers, SOA records for errors, consistency, efficiency and speed using several DNS tests.