DNSchecker is described as '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'. There are six alternatives to DNSchecker for Online / Web-based. The best alternative is intoDNS, which is free. Other great apps like DNSchecker are MxToolBox (Freemium), Dnsstuff (Freemium), DNSInspect (Free) and DNS Check (Freemium).
All of your MX record, DNS, blacklist and SMTP diagnostics in one integrated tool. Input a domain name or IP Address or Host Name. Links in the results will guide you to other relevant tools and information.
DNS Check is an application which compares the DNS records that you enter to what nameservers are returning in response to queries. If there's an issue, DNS Check will notify you, and enable you to quickly identify what it is.