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.

IsHostedBy.com - IsHostedBy is a website where you can lookup where certain websites are hosted.

DNS Propagation Check - DNS Propagation Check is an online tool that allows you to instantly perform a DNS lookup against any domain names or IP addresses.

Website Informer - Website.informer: complete data lookup & free aggregated report on any domain including whois, visitors, IP & DNS details, competitors, owners, etc

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.

NsLookup.io - A simple and powerful tool for querying DNS records